After had a great Sunday services at Mitcham Baptiste church, I played a little bit basketball with some little boys at church. Then some body suggest to have lunch in the city, so a exhausting and frustrated journey started. 6 ppl I guess we spent about 1 hour trying to find a restaurant which could celebrate Father day together. Like most American TV programs tries to tell, when things start going unsuccessfully, people start to have their opinions. Thanks God we conquered that angers from us, still had a pretty good lunch even though its place was not terrific, you know what kind of food you could get from food court. I mean food court. Chatting was great.
The down point of today is the moment I called my dad tried to said “Happy father's day." However, he interrupt my by question about my English Friend. Even though I did little be upset by his argument, I still wish he could have a good Father's day.
I think it's time to back to the track now.
2012年9月2日星期日
2012年8月17日星期五
Phrasal Verbs
English speaking countries like Australia, people uses a lot of phrasal Verbs, at the beginning you may feel very strange about it, thought all the words are very simple and familiar, your mind just couldn't catch up with them.
Don't worry about it, because they are using phrasal verbs.
sourcing from:http://www.englishclub.com/vocabulary/phrasal-verbs-list.htm
Br.E.: British English; N.Amer.: North American
sourcing from:http://www.englishclub.com/vocabulary/phrasal-verbs-list.htm
Phrasal Verbs List
Phrasal verbs are usually two-word phrases consisting of verb + adverb or verb + preposition. Think of them as you would any other English vocabulary. Study them as you come across them, rather than trying to memorize many at once. Use the list below as a reference guide when you find an expression that you don't recognize. The examples will help you understand the meanings. If you think of each phrasal verb as a separate verb with a specific meaning, you will be able to remember it more easily. Like many other verbs, phrasal verbs often have more than one meaning.
This list shows about 200 common phrasal verbs, with
meanings and examples. Only the most usual meanings are given. Some
phrasal verbs may have additional meanings.
As well as learning their meanings, you need to learn how to use
phrasal verbs properly. Some phrasal verbs require a direct object (someone/something), while others do not. Some phrasal verbs can be separated by the object, while others cannot. Review this phrasal verbs grammar from time to time so that you don't forget the rules!| Verb | Meaning | Example | |
| ask someone out | invite on a date | Brian asked Judy out to dinner and a movie. | |
| ask around | ask many people the same question | I asked around but nobody has seen my wallet. | |
| add up to something | equal | Your purchases add up to $205.32. | |
| back something up | reverse | You'll have to back up your car so that I can get out. | |
| back someone up | support | My wife backed me up over my decision to quit my job. | |
| blow up | explode | The racing car blew up after it crashed into the fence. | |
| blow something up | add air | We have to blow 50 balloons up for the party. | |
| break down | stop functioning (vehicle, machine) | Our car broke down at the side of the highway in the snowstorm. | |
| break down | get upset | The woman broke down when the police told her that her son had died. | |
| break something down | divide into smaller parts | Our teacher broke the final project down into three separate parts. | |
| break in | force entry to a building | Somebody broke in last night and stole our stereo. | |
| break into something | enter forcibly | The firemen had to break into the room to rescue the children. | |
| break something in | wear something a few times so that it doesn't look/feel new | I need to break these shoes in before we run next week. | |
| break in | interrupt | The TV station broke in to report the news of the president's death. | |
| break up | end a relationship | My boyfriend and I broke up before I moved to America. | |
| break up | start laughing (informal) | The kids just broke up as soon as the clown started talking. | |
| break out | escape | The prisoners broke out of jail when the guards weren't looking. | |
| break out in something | develop a skin condition | I broke out in a rash after our camping trip. | |
| bring someone down | make unhappy | This sad music is bringing me down. | |
| bring someone up | raise a child | My grandparents brought me up after my parents died. | |
| bring something up | start talking about a subject | My mother walks out of the room when my father brings up sports. | |
| bring something up | vomit | He drank so much that he brought his dinner up in the toilet. | |
| call around | phone many different places/people | We called around but we weren't able to find the car part we needed. | |
| call someone back | return a phone call | I called the company back but the offices were closed for the weekend. | |
| call something off | cancel | Jason called the wedding off because he wasn't in love with his fiancé. | |
| call on someone | ask for an answer or opinion | The professor called on me for question 1. | |
| call on someone | visit someone | We called on you last night but you weren't home. | |
| call someone up | phone | Give me your phone number and I will call you up when we are in town. | |
| calm down | relax after being angry | You are still mad. You need to calm down before you drive the car. | |
| not care for someone/something | not like (formal) | I don't care for his behaviour. | |
| catch up | get to the same point as someone else | You'll have to run faster than that if you want to catch up with Marty. | |
| check in | arrive and register at a hotel or airport | We will get the hotel keys when we check in. | |
| check out | leave a hotel | You have to check out of the hotel before 11:00 AM. | |
| check someone/something out | look at carefully, investigate | The company checks out all new employees. | |
| check out someone/something | look at (informal) | Check out the crazy hair on that guy! | |
| cheer up | become happier | She cheered up when she heard the good news. | |
| cheer someone up | make happier | I brought you some flowers to cheer you up. | |
| chip in | help | If everyone chips in we can get the kitchen painted by noon. | |
| clean something up | tidy, clean | Please clean up your bedroom before you go outside. | |
| come across something | find unexpectedly | I came across these old photos when I was tidying the closet. | |
| come apart | separate | The top and bottom come apart if you pull hard enough. | |
| come down with something | become sick | My nephew came down with chicken pox this weekend. | |
| come forward | volunteer for a task or to give evidence | The woman came forward with her husband's finger prints. | |
| come from somewhere | originate in | The art of origami comes from Asia. | |
| count on someone/something | rely on | I am counting on you to make dinner while I am out. | |
| cross something out | draw a line through | Please cross out your old address and write your new one. | |
| cut back on something | consume less | My doctor wants me to cut back on sweets and fatty foods. | |
| cut something down | make something fall to the ground | We had to cut the old tree in our yard down after the storm. | |
| cut in | interrupt | Your father cut in while I was dancing with your uncle. | |
| cut in | pull in too closely in front of another vehicle | The bus driver got angry when that car cut in. | |
| cut in | start operating (of an engine or electrical device) | The air conditioner cuts in when the temperature gets to 22°C. | |
| cut something off | remove with something sharp | The doctors cut off his leg because it was severely injured. | |
| cut something off | stop providing | The phone company cut off our phone because we didn't pay the bill. | |
| cut someone off | take out of a will | My grandparents cut my father off when he remarried. | |
| cut something out | remove part of something (usually with scissors and paper) | I cut this ad out of the newspaper. | |
| do someone/something over | beat up, ransack (Br.E., informal) | He's lucky to be alive. His shop was done over by a street gang. | |
| do something over | do again (N.Amer.) | My teacher wants me to do my essay over because she doesn't like my topic. | |
| do away with something | discard | It's time to do away with all of these old tax records. | |
| do something up | fasten, close | Do your coat up before you go outside. It's snowing! | |
| dress up | wear nice clothing | It's a fancy restaurant so we have to dress up. | |
| drop back | move back in a position/group | Andrea dropped back to third place when she fell off her bike. | |
| drop in/by/over | come without an appointment | I might drop in/by/over for tea sometime this week. | |
| drop someone/something off | take someone/something somewhere and leave them/it there | I have to drop my sister off at work before I come over. | |
| drop out | quit a class, school etc | I dropped out of Science because it was too difficult. | |
| eat out | eat at a restaurant | I don't feel like cooking tonight. Let's eat out. | |
| end up | eventually reach/do/decide | We ended up renting a movie instead of going to the theatre. | |
| fall apart | break into pieces | My new dress fell apart in the washing machine. | |
| fall down | fall to the ground | The picture that you hung up last night fell down this morning. | |
| fall out | separate from an interior | The money must have fallen out of my pocket. | |
| fall out | (of hair, teeth) become loose and unattached | His hair started to fall out when he was only 35. | |
| figure something out | understand, find the answer | I need to figure out how to fit the piano and the bookshelf in this room. | |
| fill something in | to write information in blanks (Br.E.) | Please fill in the form with your name, address, and phone number. | |
| fill something out | to write information in blanks (N.Amer.) | The form must be filled out in capital letters. | |
| fill something up | fill to the top | I always fill the water jug up when it is empty. | |
| find out | discover | We don't know where he lives. How can we find out? | |
| find something out | discover | We tried to keep the time of the party a secret, but Samantha found it out. | |
| get something across/over | communicate, make understandable | I tried to get my point across/over to the judge but she wouldn't listen. | |
| get along/on | like each other | I was surprised how well my new girlfriend and my sister got along/on. | |
| get around | have mobility | My grandfather can get around fine in his new wheelchair. | |
| get away | go on a vacation | We worked so hard this year that we had to get away for a week. | |
| get away with something | do without being noticed or punished | Jason always gets away with cheating in his maths tests. | |
| get back | return | We got back from our vacation last week. | |
| get something back | receive something you had before | Liz finally got her Science notes back from my room-mate. | |
| get back at someone | retaliate, take revenge | My sister got back at me for stealing her shoes. She stole my favourite hat. | |
| get back into something | become interested in something again | I finally got back into my novel and finished it. | |
| get on something | step onto a vehicle | We're going to freeze out here if you don't let us get on the bus. | |
| get over something | recover from an illness, loss, difficulty | I just got over the flu and now my sister has it. | |
| get over something | overcome a problem | The company will have to close if it can't get over the new regulations. | |
| get round to something | finally find time to do (N.Amer.: get around to something) | I don't know when I am going to get round to writing the thank you cards. | |
| get together | meet (usually for social reasons) | Let's get together for a BBQ this weekend. | |
| get up | get out of bed | I got up early today to study for my exam. | |
| get up | stand | You should get up and give the elderly man your seat. | |
| give someone away | reveal hidden information about someone | His wife gave him away to the police. | |
| give someone away | take the bride to the altar | My father gave me away at my wedding. | |
| give something away | ruin a secret | My little sister gave the surprise party away by accident. | |
| give something away | give something to someone for free | The library was giving away old books on Friday. | |
| give something back | return a borrowed item | I have to give these skates back to Franz before his hockey game. | |
| give in | reluctantly stop fighting or arguing | My boyfriend didn't want to go to the ballet, but he finally gave in. | |
| give something out | give to many people (usually at no cost) | They were giving out free perfume samples at the department store. | |
| give something up | quit a habit | I am giving up smoking as of January 1st. | |
| give up | stop trying | My maths homework was too difficult so I gave up. | |
| go after someone | follow someone | My brother tried to go after the thief in his car. | |
| go after something | try to achieve something | I went after my dream and now I am a published writer. | |
| go against someone | compete, oppose | We are going against the best soccer team in the city tonight. | |
| go ahead | start, proceed | Please go ahead and eat before the food gets cold. | |
| go back | return to a place | I have to go back home and get my lunch. | |
| go out | leave home to go on a social event | We're going out for dinner tonight. | |
| go out with someone | date | Jesse has been going out with Luke since they met last winter. | |
| go over something | review | Please go over your answers before you submit your test. | |
| go over | visit someone nearby | I haven't seen Tina for a long time. I think I'll go over for an hour or two. | |
| go without something | suffer lack or deprivation | When I was young, we went without winter boots. | |
| grow apart | stop being friends over time | My best friend and I grew apart after she changed schools. | |
| grow back | regrow | My roses grew back this summer. | |
| grow up | become an adult | When Jack grows up he wants to be a fireman. | |
| grow out of something | get too big for | Elizabeth needs a new pair of shoes because she has grown out of her old ones. | |
| grow into something | grow big enough to fit | This bike is too big for him now, but he should grow into it by next year. | |
| hand something down | give something used to someone else | I handed my old comic books down to my little cousin. | |
| hand something in | submit | I have to hand in my essay by Friday. | |
| hand something out | to distribute to a group of people | We will hand out the invitations at the door. | |
| hand something over | give (usually unwillingly) | The police asked the man to hand over his wallet and his weapons. | |
| hang in | stay positive (N.Amer., informal) | Hang in there. I'm sure you'll find a job very soon. | |
| hang on | wait a short time (informal) | Hang on while I grab my coat and shoes! | |
| hang out | spend time relaxing (informal) | Instead of going to the party we are just going to hang out at my place. | |
| hang up | end a phone call | He didn't say goodbye before he hung up. | |
| hold someone/something back | prevent from doing/going | I had to hold my dog back because there was a cat in the park. | |
| hold something back | hide an emotion | Jamie held back his tears at his grandfather's funeral. | |
| hold on | wait a short time | Please hold on while I transfer you to the Sales Department. | |
| hold onto someone/something | hold firmly using your hands or arms | Hold onto your hat because it's very windy outside. | |
| hold someone/somethingup | rob | A man in a black mask held the bank up this morning. | |
| keep on doing something | continue doing | Keep on stirring until the liquid comes to a boil. | |
| keep something from someone | not tell | We kept our relationship from our parents for two years. | |
| keep someone/something out | stop from entering | Try to keep the wet dog out of the living room. | |
| keep something up | continue at the same rate | If you keep those results up you will get into a great college. | |
| let someone down | fail to support or help, disappoint | I need you to be on time. Don't let me down this time. | |
| let someone in | allow to enter | Can you let the cat in before you go to school? | |
| look after someone/something | take care of | I have to look after my sick grandmother. | |
| look down on someone | think less of, consider inferior | Ever since we stole that chocolate bar your dad has looked down on me. | |
| look for someone/something | try to find | I'm looking for a red dress for the wedding. | |
| look forward to something | be excited about the future | I'm looking forward to the Christmas break. | |
| look into something | investigate | We are going to look into the price of snowboards today. | |
| look out | be careful, vigilant, and take notice | Look out! That car's going to hit you! | |
| look out for someone/something | be especially vigilant for | Don't forget to look out for snakes on the hiking trail. | |
| look something over | check, examine | Can you look over my essay for spelling mistakes? | |
| look something up | search and find information in a reference book or database | We can look her phone number up on the Internet. | |
| look up to someone | have a lot of respect for | My little sister has always looked up to me. | |
| make something up | invent, lie about something | Josie made up a story about why we were late. | |
| make up | forgive each other | We were angry last night, but we made up at breakfast. | |
| make someone up | apply cosmetics to | My sisters made me up for my graduation party. | |
| mix something up | confuse two or more things | I mixed up the twins' names again! | |
| pass away | die | His uncle passed away last night after a long illness. | |
| pass out | faint | It was so hot in the church that an elderly lady passed out. | |
| pass something out | give the same thing to many people | The professor passed the textbooks out before class. | |
| pass something up | decline (usually something good) | I passed up the job because I am afraid of change. | |
| pay someone back | return owed money | Thanks for buying my ticket. I'll pay you back on Friday. | |
| pay for something | be punished for doing something bad | That bully will pay for being mean to my little brother. | |
| pick something out | choose | I picked out three sweaters for you to try on. | |
| point someone/something out | indicate with your finger | I'll point my boyfriend out when he runs by. | |
| put something down | put what you are holding on a surface or floor | You can put the groceries down on the kitchen counter. | |
| put someone down | insult, make someone feel stupid | The students put the substitute teacher down because his pants were too short. | |
| put something off | postpone | We are putting off our trip until January because of the hurricane. | |
| put something out | extinguish | The neighbours put the fire out before the firemen arrived. | |
| put something together | assemble | I have to put the crib together before the baby arrives. | |
| put up with someone/something | tolerate | I don't think I can put up with three small children in the car. | |
| put something on | put clothing/accessories on your body | Don't forget to put on your new earrings for the party. | |
| run into someone/something | meet unexpectedly | I ran into an old school-friend at the mall. | |
| run over someone/something | drive a vehicle over a person or thing | I accidentally ran over your bicycle in the driveway. | |
| run over/through something | rehearse, review | Let's run over/through these lines one more time before the show. | |
| run away | leave unexpectedly, escape | The child ran away from home and has been missing for three days. | |
| run out | have none left | We ran out of shampoo so I had to wash my hair with soap. | |
| send something back | return (usually by mail) | My letter got sent back to me because I used the wrong stamp. | |
| set something up | arrange, organize | Our boss set a meeting up with the president of the company. | |
| set someone up | trick, trap | The police set up the car thief by using a hidden camera. | |
| shop around | compare prices | I want to shop around a little before I decide on these boots. | |
| show off | act extra special for people watching (usually boastfully) | He always shows off on his skateboard | |
| sleep over | stay somewhere for the night (informal) | You should sleep over tonight if the weather is too bad to drive home. | |
| sort something out | organize, resolve a problem | We need to sort the bills out before the first of the month. | |
| stick to something | continue doing something, limit yourself to one particular thing | You will lose weight if you stick to the diet. | |
| switch something off | stop the energy flow, turn off | The light's too bright. Could you switch it off. | |
| switch something on | start the energy flow, turn on | We heard the news as soon as we switched on the car radio. | |
| take after someone | resemble a family member | I take after my mother. We are both impatient. | |
| take something apart | purposely break into pieces | He took the car brakes apart and found the problem. | |
| take something back | return an item | I have to take our new TV back because it doesn't work. | |
| take off | start to fly | My plane takes off in five minutes. | |
| take something off | remove something (usually clothing) | Take off your socks and shoes and come in the lake! | |
| take something out | remove from a place or thing | Can you take the garbage out to the street for me? | |
| take someone out | pay for someone to go somewhere with you | My grandparents took us out for dinner and a movie. | |
| tear something up | rip into pieces | I tore up my ex-boyfriend's letters and gave them back to him. | |
| think back | remember (often + to, sometimes + on) | When I think back on my youth, I wish I had studied harder. | |
| think something over | consider | I'll have to think this job offer over before I make my final decision. | |
| throw something away | dispose of | We threw our old furniture away when we won the lottery. | |
| turn something down | decrease the volume or strength (heat, light etc) | Please turn the TV down while the guests are here. | |
| turn something down | refuse | I turned the job down because I don't want to move. | |
| turn something off | stop the energy flow, switch off | Your mother wants you to turn the TV off and come for dinner. | |
| turn something on | start the energy, switch on | It's too dark in here. Let's turn some lights on. | |
| turn something up | increase the volume or strength (heat, light etc) | Can you turn the music up? This is my favourite song. | |
| turn up | appear suddenly | Our cat turned up after we put posters up all over the neighbourhood. | |
| try something on | sample clothing | I'm going to try these jeans on, but I don't think they will fit. | |
| try something out | test | I am going to try this new brand of detergent out. | |
| use something up | finish the supply | The kids used all of the toothpaste up so we need to buy some more. | |
| wake up | stop sleeping | We have to wake up early for work on Monday. | |
| warm someone/something up | increase the temperature | You can warm your feet up in front of the fireplace. | |
| warm up | prepare body for exercise | I always warm up by doing sit-ups before I go for a run. | |
| wear off | fade away | Most of my make-up wore off before I got to the party. | |
| work out | exercise | I work out at the gym three times a week. | |
| work out | be successful | Our plan worked out fine. | |
| work something out | make a calculation | We have to work out the total cost before we buy the house. | |
2010年10月11日星期一
php tutor shopping cart session
http://www.phpwebcommerce.com/shopping-cart-source-code.php
实例/example web:http://www.phpwebcommerce.com/plaincart/index.php?c=14
http://v3.thewatchmakerproject.com/journal/276/building-a-simple-php-shopping-cart
实例/example web:http://www.phpwebcommerce.com/plaincart/index.php?c=14
http://v3.thewatchmakerproject.com/journal/276/building-a-simple-php-shopping-cart
php shopping cart code
Building a simple PHP shopping cart
Nov 21 2005
Update 21/11: I’ve added a demo and downloadable .zip file at the end of the article.
Update 07/12: Thanks to Greg and Rob Shan Lone for spotting a bug in the cart update code – I’ve now fixed this and updated the demo and .zip file; thanks guys!
One of the most common requirements any web designer/developer will come across is likely to be that of the small business taking its first steps online; a client with an established widget-selling company now wants to move into the national market and sell their widgets to the world.
What they need to do this (apart from a great-looking, functional, usable and accessible website!) is some sort of shopping-cart system to allow their customers to add, remove and update the products they wish to buy.
This article will walk through the simple steps to achieve this, using the server-side language PHP and a MySQL database.
Setting up the database
Let’s take as our example a bookseller. They are not the best-stocked bookseller in the world, having as they do only three titles in stock, but it is enough for our example. Let’s create the database and add some stock:
1. CREATE TABLE books (
2. id int(6) unsigned NOT NULL auto_increment,
3. title varchar(100) NOT NULL default '',
4. author varchar(100) NOT NULL default '',
5. price decimal(3,2) NOT NULL default '0.00',
6. PRIMARY KEY (id)
7. ) TYPE=MyISAM;
8.
9. INSERT INTO books VALUES (1, 'Where God Went Wrong', 'Oolon Colluphid', '24.99');
10. INSERT INTO books VALUES (2, 'Some More of God\'s Greatest Mistakes', 'Oolon Colluphid', '17.99');
11. INSERT INTO books VALUES (3, 'Who Is This God Person Anyway?', 'Oolon Colluphid', '14.99');
12. Download this code: /code/php-cart-1.txt
Now that step is out of the way, let’s create our shopping cart.
Identify our requirements
The cart we are going to build should be pretty familiar to most internet users. It will provide a means of displaying a message on every page of the site (along the lines of “You have 5 items in your shopping cart”), which when clicked will take the customer to a list of the items in the cart; each item may be removed or have its quantity updated.
As all of our stock details are stored in the database, the only piece of information that we need to store about each customer is the id of each product they have added to their cart. To do this, we are going to use PHP’s built-in session handling capabilities.
Using sessions in PHP
PHP’s session handling is very easy to understand.
To ‘switch it on’, simply add session_start(); at the top of your code; you can then store values (or arrays) in session variables:
$_SESSION['name'] = 'Matthew'; $_SESSION['age'] = 31;
These $_SESSION variables will now be available to any PHP scripts on other pages (as long as you’ve included the session_start(); call first).
A short note on cookies
The default behaviour of PHP sessions is to store the session ID (a long string of numbers and letters that identifies you to the server) as a cookie on your computer; however, even if you have cookies disabled this functionality will still work – PHP will instead append the session ID to each link on the site (in the form ‘mypage.php?PHPSESSID=’) so that it can continue to accurately track visitors from page to page.
Creating the cart
We will store the contents of the shopping cart as a comma-separated list of product ids in a session named (unsurprisingly) ‘cart’ – for example, a cart containing “1,1,3,1,2” has four items; three of product #1, and one each of products #2 and #3.
Firstly, let’s create the code to display the “You have X items…” message on every page:
1. function writeShoppingCart() {
2. $cart = $_SESSION['cart'];
3. if (!$cart) {
4. return '
5. } else {
6. // Parse the cart session variable
7. $items = explode(',',$cart);
8. $s = (count($items) > 1) ? 's':'';
9. return '
10. }
11. }
12.
13. Download this code: /code/php-cart-2.txt
This function first gets the value of the ‘cart’ session variable into a local variable, mainly to save on typing. If the cart is empty, we return an appropriate message; if not, we use the explode() function to create an array of all the products in the cart, and then count() them and display the result (the $s variable is there to make plurals display correctly).
Now we can display the correct message anywhere on the site:
echo writeShoppingCart();
I hope that made sense; let’s move on to displaying the contents of the cart itself.
Show me the money
The shopping cart page itself (cart.php) can be arrived at in a couple of ways. The user may have clicked on the link created by the writeShoppingCart() function above; or, they may have clicked an ‘Add to cart’ link on a product page.
If it was the latter, we need to intercept that click and update our cart contents before displaying the new list of products – simple enough, as all we need to do is append the id of the clicked product to the ‘cart’ session variable. Our product links are going to look like this:
Add to cart
Don’t worry about the ‘action=add’ bit, we’ll get to that later. The id can now be extracted from $_GET[‘id’] and added to our cart:
1. $cart = $_SESSION['cart'];
2. if ($cart) {
3. $cart .= ','.$_GET['id'];
4. } else {
5. $cart = $_GET['id'];
6. }
7. $_SESSION['cart'] = $cart;
8. Download this code: /code/php-cart-3.txt
Now, on to the contents of our cart!
Multiple items, one product
As in our example above, it is entirely possible that a customer might have more than one of a certain product in their cart. As we don’t want to list duplicate items when we display the contents, we need to figure out a way to combine any of the same product into one entry (with a corresponding quantity attached).
1. $cart = $_SESSION['cart'];
2. if ($cart) {
3. $items = explode(',',$cart);
4. $contents = array();
5. foreach ($items as $item) {
6. $contents[$item] = (isset($contents[$item])) ? $contents[$item] + 1 : 1;
7. }
8. Download this code: /code/php-cart-4.txt
This time, after exploding the list of product ids, we have iterated through them to create a new array named $contents, which consists of key=>value pairs where the key is the product id and the value is the quantity of that product in the shopping cart. So to take our example above, a cart containing “1,1,3,1,2” would become an array where ‘1’=>3, ‘2’=>1, ‘3’=>1.
Now that we have an accurate count of unique products, let’s query the product database for each one and output its details into a table:
1. $total = 0;
2. $output[] = '';
';
18. $output[] = '
19.
20. Download this code: /code/php-cart-5.txt
(*Note*: I’m using a PHP class to handle my database connections, so your code may need to be slightly different).
Pretty simple stuff – we iterate through the new $contents array and query the database for each product id. Then we output the relevant details for each product; title, author and price, and at the bottom we show the grand total for the order. For each item, we’ve also included a link to remove the item from the cart, a textbox containing the current quantity of that item, and a total price (obviously this will only differ from the base price if the quantity is not 1).
The reason I’m using $output[] = ... is that I am buffering the output into an array to print to the screen later.
So far so good – now how about removing products from the cart?
Deleting a product
As shown above, the link to delete a product from the cart follows the same format as the ‘add a product’ link:
Remove
Let’s expand on the code from earlier by adding a switch() statement to handle the different things that might happen to our cart:
1. $cart = $_SESSION['cart'];
2. $action = $_GET['action'];
3. switch ($action) {
4. case 'add':
5. if ($cart) {
6. $cart .= ','.$_GET['id'];
7. } else {
8. $cart = $_GET['id'];
9. }
10. break;
11. case 'delete':
12. if ($cart) {
13. $items = explode(',',$cart);
14. $newcart = '';
15. foreach ($items as $item) {
16. if ($_GET['id'] != $item) {
17. if ($newcart != '') {
18. $newcart .= ','.$item;
19. } else {
20. $newcart = $item;
21. }
22. }
23. }
24. $cart = $newcart;
25. }
26. break;
27. }
28. $_SESSION['cart'] = $cart;
29. Download this code: /code/php-cart-6.txt
The new ‘delete’ case iterates through the ‘cart’ session, looking for any product ids that AREN’T the one we’re deleting, and adding them to a temporary variable called $newcart. When it’s finished, it puts the revised cart contents back into $cart.
Updating a product
Lastly, we are going to allow customers to update the contents of their shopping cart by manually changing the value in the quantity box for each product.
To make this work, we’ll wrap the shopping cart table in a ';
21. Download this code: /code/php-cart-7.txt
Note that, even though the form uses the POST method, its action includes a GET variable, “action=update”. Again, we can expand our previous code to process any quantity updates:
1. case 'update':
2. if ($cart) {
3. $newcart = '';
4. foreach ($_POST as $key=>$value) {
5. if (stristr($key,'qty')) {
6. $id = str_replace('qty','',$key);
7. $items = ($newcart != '') ? explode(',',$newcart) : explode(',',$cart);
8. $newcart = '';
9. foreach ($items as $item) {
10. if ($id != $item) {
11. if ($newcart != '') {
12. $newcart .= ','.$item;
13. } else {
14. $newcart = $item;
15. }
16. }
17. }
18. for ($i=1;$i<=$value;$i++) {
19. if ($newcart != '') {
20. $newcart .= ','.$id;
21. } else {
22. $newcart = $id;
23. }
24. }
25. }
26. }
27. }
28. $cart = $newcart;
29. break;
30.
31. Download this code: /code/php-cart-8.txt
This looks quite complicated, but it’s fairly straightforward; we interrogate the contents of the $_POST array (which holds all our quantity values) and extract the relevant id and value pairs. For each product, we then delete all the existing instances of it, and re-insert the new quantity.
There are a number of ways this could have been done – for example, by counting the existing number of each product present in the cart and figuring out whether we needed to add or remove items – but this seemed the easiest way to process the quantity updates.
Summary
And that’s about it! A functional and easy shopping cart script – here’s the final function to display the contents of the cart:
1. function showCart() {
2. $cart = $_SESSION['cart'];
3. if ($cart) {
4. $items = explode(',',$cart);
5. $contents = array();
6. foreach ($items as $item) {
7. $contents[$item] = (isset($contents[$item])) ? $contents[$item] + 1 : 1;
8. }
9. $output[] = '';
29. } else {
30. $output[] = '
31. }
32. return join('',$output);
33. }
34. Download this code: /code/php-cart-9.txt
Note that if the cart is empty, a suitable message is displayed.
A working demo can be seen (excuse the lack of design!), or please feel free to download a .zip of all the files – any questions, comments or suggestions on how the code could be improved gratefully received.
Filed under: PHP, MySQL.
Technorati tags: php mysql php shopping cart
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Comments
Matthijs
1782 days ago
Nice article! A good explanation for how the basics of a shopping cart work. That’ll help us on our way. Thanks.
#1
Christian Montoya
1779 days ago
Awesome. I bookmarked this for later.
#2
Hamish Keith
1774 days ago
Very very good – prob the best i have seen on the web
#3
Andrew
1769 days ago
Thank you so much for this tutorial. It was exactly what I’d been looking for for some time. Great design as well. Beautifully done.
#4
Greg Hamilton
1769 days ago
First of all wicked article, very helpful. Whats the best way to attempt the checkout ? Thanks
#5
Matthew Pennell
1769 days ago
Greg: Funny you should ask that, as I wrote an article that kind of touches on the subject – it is specific to Textpattern, but there is a section on ‘Shopping Integration’ that covers using PayPal to handle payment.
As we’re doing the shoppng cart bit ourselves, we could use PayPal’s new API to simply send the payment details and receive back the response (or whatever other payment processor we’re using).
#6
Greg Hamilton
1769 days ago
Hey Matt thanks for the with the checkout help, quick question about the update function..when you try to update an id that isn’t qty1 it doesnt update…not sure if I messed up the demo file or not :( thanks
#7
Greg Hamilton
1769 days ago
Sorry Matt I mean if you have, lets say two products in yer cart and you try to update the top one it doesnt, but the bottom one will. I think it does it in the demo as well….thanks bud
#8
Matthew Pennell
1768 days ago
Thanks, Greg – I’ve fixed the problem and updated the demo and .zip.
#9
Greg Hamilton
1766 days ago
Hey again Matt
Quick question about quantities, is ti possible to add a function that also allows the user to add quantities inside the product view before adding to cart. Thanks bud
#10
Matthew Pennell
1766 days ago
It would be very easy, Greg, although I don’t have time to do it right now – perhaps a later expansion, unless you want to add it in and publish your changes?
#11
Greg Hamilton
1766 days ago
Ya I’m gonna give it a go. I’ll publish when I get it all set to go.
#12
Andrew
1764 days ago
Hi,
Thanks for the tutorial!
i have changed the cart.php page a little. on the cart.php page, if the user clicks re-fresh, an item is added to the the cart as the ID ifor the product is stored in the querystring. its easily fixed.
Just a heads up for some.
Once again thanks for the demo!
#13
Viktor
1761 days ago
Great tutorial. Most tutorials takes too many steps at the same time so you only end up comfused, but this is vert easy to follow and understand.
#14
hidayat
1744 days ago
Good job boss
it’s nice tutorial ,too nice
#15
Franco
1743 days ago
Hi Matthew,
I test your script
but when i add to cart
this is message page:
Please check quantities…
You shopping cart is empty
I don’t see any product choice.
Can you help me?
Regards and happy New year
Franco
#16
Matthew Pennell
1742 days ago
Hi Franco – I’d need a bit more information to work out what might be wrong; the first thing to try though would be to echo the $id and $cart variables as the code progresses through the ‘add’ routine to see what is happening.
#17
The Illumidigerati
1735 days ago
Matt, does this cart form allow enough security for actual business transactions in the form of moneyorder/personal check? I’ll be webmastering my girlfriends home business and starting out neither of us are really keen on dealing with credit or any online payment ventures, i.e. paypal. Is there a reason for anything more secure when moneyorders/personal checks are the only payment methods since only user information will be logged, not CC info or bank account info?
#18
Matthew Pennell
1735 days ago
This cart script doesn’t handle any kind of payment; it is only for keeping track of what is in the shopping cart.
#19
dreamer85
1734 days ago
good tutorial well done
if it explaines how to display image with the products will be greate tutorial
take care
#20
Momotaro
1725 days ago
Excellent tutorial.
I’d like to know how to display the result in a Form that could then be saved to .csv file server-side? Ultimately, even send me an email when order Form was submited. The tutorials I’ve come across in past were too full of tech-speak that I couldn’t understand.
#21
Aneurin
1720 days ago
Thank You for the tutorial…
i was wondering if i could add product option to this shopping cart..eg. same item(same product id) but different options (size,colour)...i would appreciate some ideas…thanks in advance…
#22
Matthew Pennell
1720 days ago
Aneurin: Yes, that’s certainly an option; the project that I developed this cart code for does just that.
I used certain characters to split the product that was added to the cart, so to take your example of something with a certain size and colour, I would store the sizes and colours in their own tables in the database, then add products in the format “123c6s3”, which would translate as “Product #123, colour #6, size #3”.
The show-cart page would then lookup that colour and size from the table as part of the SQL statement and display the correct description of the product.
#23
Matthew Pennell
1720 days ago
Momotaro: Sending an email when the order is submitted would be pretty simple � the PHP mail() function covers that in detail.
#24
Aneurin
1719 days ago
Thank You very much…...
#25
momotaro
1717 days ago
Thanks for the link
#26
junwei
1709 days ago
nice! It help me alot, u mind adding add to cart and login function . thank
#27
Cormac
1708 days ago
are there anyother api’s that could be intergrated fairly easily with this shopping cart other than PayPal’s ?
#28
Matthew Pennell
1708 days ago
Cormac: There are quite a few online payment mechanisms that are as easy to integrate with as PayPal. WorldPay is probably the next best known one, but there are plenty around.
#29
Matt Cooper
1702 days ago
Nice code, and I very much like your website too, very fresh design. One disappointment (only a small one!) is that you haven’t provided further code for a checkout…is this on the cards? Good luck…
#30
Tan
1700 days ago
Great Demo, the best on the web!
I have one problem, same as franco above, I select add item and it displays check quantities on the cart page, with no items passed through. I have had a look over every page to no avail, would it be a function issue? It passes the id through the url but does not display it.
#31
James
1695 days ago
Hi Matt,
I’m new to all this and am pulling my hair out! – it just won’t work for me – getting messages such as:
Query failed: Unknown column ‘Array’ in ‘where clause’ SQL: SELECT * FROM book WHERE id = Array
or…
Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result
or…
Warning: mysql_num_rows(): supplied argument is not a valid MySQL
Where am I going wrong – from the other comments it seems to be pretty easy so it must be something I’m doing wrong!
Thanks for any help – very frstrated at the moment!
James
#32
Matthew Pennell
1695 days ago
James: That sounds as if the id is not being passed through in the querystring correctly. Check that you have populated the database correctly and have configured your database connection information properly.
#33
tan
1694 days ago
Just me again, why would it not display in the cart. Please note above note.
#34
Matthew Pennell
1694 days ago
Tan: It sounds as if the id variable in the querystring is not being picked up by the code (php-cart-3 in the code above) and added to the cart.
You could try adding a loop through all the items in the GET collection:
foreach ($_GET as $key => $value) {
echo $key . � contains � . $value . '
';
}
That will list everything all the variables in the querystring; if nothing is there, it may be that you�ve changed the form method to �post� instead of �get�? Or possibly you're using a very old version of PHP that doesn't support $_GET - you could try the above code with $HTTP_GET_VARS instead; if that works you'll have to change all instances of $_GET to $HTTP_GET_VARS (or upgrade to a host supporting a more modern version of PHP!)
#35
CHiNo4ReaL
1692 days ago
Nice tutorial, I’m gonna use it, but I have a question, is it possible to create catogory’s,
#36
Matthew Pennell
1692 days ago
Chino: Do you mean in the products listings, or in the cart session variable?
It depends how your database is set up whether you’d need any additional work to cope with categories.
#37
G
1692 days ago
Hello,
I have installed your cart on my website, but I have a problem. When I navigate between cart.php and index.php it appears this error message:
“Warning: session_start(): Cannot send session cache limiter – headers already sent (output started at ….global.inc.php:9) in cart.php on line 9”
“Warning: session_start(): Cannot send session cache limiter – headers already sent ”...
Can you please help me to solve it out?
Regards,
G.
#38
CHiNo4ReaL
1691 days ago
@Matthew
Yes, because i’m creating a webshop, with carparts, so there are a few catorgies, like exterior, frontbumpers, rims etc.
#39
CHiNo4ReaL
1691 days ago
Oh and another question, How can I finish the order?
#40
Matthew Pennell
1691 days ago
G: The session_start() command has to appear in the code before any output has been sent to the browser. As your error says, there is output being sent at line 9 of global.inc.php – you must have changed the source files, as my originals only have database connection variables in that file.
#41
Matthew Pennell
1691 days ago
Chino: Bear in mind that the id of the product that is held in the cart doesn’t have to include any reference to the category it is in.
You just have to alter the products database to include a category field; you can then use that when listing products, but just use the product id to hold it in the cart.
To finish the order, you’re going to have to decide what you want to do with it – either have it saved to a database, emailed to you, or processed by an online payment processor like PayPal. That’s beyond the scope of this tutorial, though.
#42
CHiNo4ReaL
1690 days ago
Ok, Do you have an example for the catorgyfield in the database?
#43
jatty5
1690 days ago
Hi all, I am new to this php and am trying to buid a shopping cart for my business myself. I have installed easyphp which has given me apache mysql and php, and am trying to work through this tutorial which I think is excellent for somebody like me a total novice! I have managed to create the database succesfully by copy the complete script and putting it through phpmyadmin. I tried to download the complete zip files, but where do i put them and how on earth do i set the database connection files up. Please help as I am getting alittle lost. I have also downloaded each script but agian where does it go, i know it would be in the WWW directory of my easyphp folder. Please help
#44
Matthew Pennell
1689 days ago
Chino: Just add a category field into your database using whatever MySQL admin tool you’re using.
#45
Matthew Pennell
1689 days ago
jatty5: If you have downloaded the zip you don’t need the individual scripts; just unpack the zip file to a folder under your www directory (e.g. “cart”). The database connection settings are in inc/global.inc.php if you need to change them, but if you’re running it locally the settings should be fine.
Then visit http://localhost/cart/ and it should all be working (you may have to start the PHP and MySQL services, depending on the package you are using).
#46
jatty5
1689 days ago
Hi Mathew, thanks for your swift reply, i have done what you said but still get the following reply:
I take it it has something to do with the database i created the database under phpmyadmin and called the database wtchproject and then run your script under that which created your tables under this database.
What do i change in the gobal file and is it possible for you to show where i can make those changes if possible.
Notice: Could not select database in c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php on line 80
Warning: session_start(): Cannot send session cookie – headers already sent by (output started at c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php:80) in c:\program files\easyphp1-8\www\cart-demo\index.php on line 9
Warning: session_start(): Cannot send session cache limiter – headers already sent (output started at c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php:80) in c:\program files\easyphp1-8\www\cart-demo\index.php on line 9
Your Shopping Cart
Notice: Undefined index: cart in c:\program files\easyphp1-8\www\cart-demo\inc\functions.inc.php on line 3
You have no items in your shopping cart
Books In Our Store
Notice: Query failed: No database selected SQL: SELECT * FROM books ORDER BY id in c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php on line 109
Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php on line 151
Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php on line 167
#47
ScopAL
1689 days ago
Notice: Undefined index: cart in z:\home\cart\www\inc\functions.inc.php on line 3
You have no items in your shopping cart
:((((
#48
CHiNo4ReaL
1689 days ago
Jatty5
I think that you have selected the wrong database, your database is called wtchprojec, but in the script its selecting books
#49
Matthew Pennell
1689 days ago
jatty5: I would suggest that if you’re trying to learn to use PHP/MySQL, it would be a good idea to learn all about creating database connections, but here is how to fix your problem:
In global.inc.php, you have four variables that are used to create the database connection:
$host = ‘localhost’;
$user = ‘root’;
$pass = ‘’;
$name = ‘’;
These correspond to your host name (usually ‘localhost’), the username and password you are using, and the name of your database.
So in your case, just change the last line to $name=’wtchproject’; and the database connection class object will then be pointing at your database.
#50
CHiNo4ReaL
1687 days ago
If I want the order mailed to me, how can I do that?
I have tried to do that, but i cant find any good ones, can u help me?
#51
Matthew Pennell
1687 days ago
I suppose you’d have to build in some data capture for the customer’s details, and then use mail() to send everything.
I’m not building the whole site for you, though..! ;)
#52
CHiNo4ReaL
1686 days ago
ok, thanks anyway
#53
Greg Hamilton
1684 days ago
Hey again Matt, what are your feelings on using cookies instead of sessions to remember the items that are in the shopping cart, do you think its necessary at all ?
#54
Matthew Pennell
1684 days ago
Greg: The benefit would obviously be that you would be able to leave the site and come back to the same basket; an approach using both sessions and cookies would probably be a good idea (with a fairly short expiration period).
#55
Juilius
1683 days ago
Hi I am having problems with the cart.php, whenever I hit the refresh button it adds another quantity to the cart? Any ideas?
Oh by the way, great, great example!
#56
Matthew Pennell
1682 days ago
Juilius: Yes, refreshing the page will add another item to the cart due to its use of the querystring ($_GET collection) to handle addition.
You can get around it by adding an extra session variable and storing the last item added and the time it was added, then checking against that to see if it is a repeated entry within a certain timeframe.
#57
Steven
1657 days ago
I’ll be messing around with this on XAMPP soon! I’m a bit of a PHP beginner but I thinks it’s important to dive in at the deep end!
#58
Steven
1657 days ago
I’ll be messing around with this on XAMPP soon! I’m a bit of a PHP beginner but I thinks it’s important to dive in at the deep end!
PS. Edited to ask, does a shopping cart system like this have to be bolted onto a dynamic website or can I add it to static product pages?
#59
Matthew Pennell
1657 days ago
Steven: I’m not sure how you’d use it with static pages, as it relies on a database of product details – I suppose you could copy your static data into the database, but if you’re doing that you may as well be using the database to output your product info as well!
#60
Fred
1641 days ago
I’m just curious, since this code connect to the db and all. Is this vulnerable to sql injection at all?
Can users modify the input variables or the session cookie to inject special characters that could cause buffer overflow in the SQL sequence?
I don’ recall seeing anywhere that inputs are scrubbed, but I could be wrong or the way the code is written, input scrubbing might be a non-issue.
Any confirmation on this?
#61
Matthew Pennell
1640 days ago
Fred: You are correct that if you wanted to use this in a commercial setting it would be a good idea to add some validation of the session data when it is read to output the contents of the cart. This could be as simple as using preg_match to check that the ID of the product is numeric.
#62
Fred
1640 days ago
This was some amazingly great cart code which gave me a good jump on what I wanted to create. Thanks Matt.
I did add some basic sanitization code to keep the db safe from SQL injects. You can take from the following.
I added a sanitization function and then called it on certain variable inputs used in the cart program:
function sanitize_system_string($string, $min=’’, $max=’’) {
$pattern = ’/(;|\||`|>| $max)))
return FALSE;
return $string;
}
// these occur in various places
sanitize_system_string($_GET[‘id’],1,50)
$cart = sanitize_system_string($_SESSION[‘cart’]);
$action = sanitize_system_string($_GET[‘action’],1,50);
// assigned right underneath the update switch foreach loop
$key = sanitize_system_string($key,1,50);
#63
Alex
1640 days ago
Thanx for the code Fred very helpful…
#64
Fred
1639 days ago
Sorry the sanitize_system_string function got partially truncated by the comment submit form. The other examples of variable sanitization remained in tact though.
Anyway, folks can get the point. Find a sanitization function, insert it in the functions php document and then employ it throughout the cart code as needed.
I identified several good places in the last post :)
I love this cart code matt provided! It has provided me the basis to do some wonders with it!
#65
Ella
1638 days ago
Hi There,
I am fairly new to php etc and am trying to do a shopping cart as part of my final project for my degree. I am getting an error when I click the add to cart link it goes through to the cart page but has the following error:
Parse error: parse error in c:\LocalUser\fashuti\public_html\cart.php on line 174
it is erroring on the last line of code on the page which is obciously not the problem. I have adapted the code on your size so that i can distinguish by id, size and colour. My id’s are both letter and charactger based. I can understand all of the code apart from one line which confuses me and I wonder if it could relate to that?
It seems you are comparing qty which is created here to the id?
foreach ($contents as $id=>$qty) {
I wondered if this could be my problem?
I will post my cart code below:
Hi There,
I am fairly new to php etc and am trying to do a shopping cart as part of my final project for my degree. I am getting an error when I click the add to cart link it goes through to the cart page but has the following error:
Parse error: parse error in c:\LocalUser\fashuti\public_html\cart.php on line 174
it is erroring on the last line of code on the page which is obciously not the problem. I have adapted the code on your size so that i can distinguish by id, size and colour. My id’s are both letter and charactger based. I can understand all of the code apart from one line which confuses me and I wonder if it could relate to that?
It seems you are comparing qty which is created here to the id?
foreach ($contents as $id=>$qty) {
I wondered if this could be my problem?
I will post my cart code below:
$total = 0;
$output[] = ‘’;
$conn=odbc_connect(‘danum_fashu’,’’,’’);
foreach ($contents as $id=>$qty) {
$sql = ‘SELECT * FROM products, product_line WHERE products.product_id = ’.$id.’ AND products.product_id = product_line.product_id AND product_line.product_size= ’.$sz.’ AND product_line.product_colour = ’.$col;
$rs=odbc_exec($conn,$sql);
$pid=odbc_result($rs,”product_line.product_id”);
$size=odbc_result($rs,”product_line.product_size”);
$name=odbc_result($rs,”products.product_name”);
$colour=odbc_result($rs,”product_line.product_colour”);
$cost=odbc_result($rs,”products.product_costprice”);
$endcost = number_format($cost * 2.6, 2, ’.’, ’,’);
$output[] = ‘’;
$output[] = ‘’.$pid.’ by ’.$name.’’;
$output[] = ‘’.$size.’ ’.$colour.’’;
$output[] = ’£’.$endcost.’’;
$output[] = ‘’;
$output[] = ’£’.($endcost * $qty).’’;
$output[] = ‘Remove’;
$total += $endcost * $qty;
$output[] = ‘’;
}
$output[] = ‘’;
$output[] = ‘Grand total: £’.$total.’’;
odbc_close($conn);
Any help would be gratefully recieved
Nov 21 2005
Update 21/11: I’ve added a demo and downloadable .zip file at the end of the article.
Update 07/12: Thanks to Greg and Rob Shan Lone for spotting a bug in the cart update code – I’ve now fixed this and updated the demo and .zip file; thanks guys!
One of the most common requirements any web designer/developer will come across is likely to be that of the small business taking its first steps online; a client with an established widget-selling company now wants to move into the national market and sell their widgets to the world.
What they need to do this (apart from a great-looking, functional, usable and accessible website!) is some sort of shopping-cart system to allow their customers to add, remove and update the products they wish to buy.
This article will walk through the simple steps to achieve this, using the server-side language PHP and a MySQL database.
Setting up the database
Let’s take as our example a bookseller. They are not the best-stocked bookseller in the world, having as they do only three titles in stock, but it is enough for our example. Let’s create the database and add some stock:
1. CREATE TABLE books (
2. id int(6) unsigned NOT NULL auto_increment,
3. title varchar(100) NOT NULL default '',
4. author varchar(100) NOT NULL default '',
5. price decimal(3,2) NOT NULL default '0.00',
6. PRIMARY KEY (id)
7. ) TYPE=MyISAM;
8.
9. INSERT INTO books VALUES (1, 'Where God Went Wrong', 'Oolon Colluphid', '24.99');
10. INSERT INTO books VALUES (2, 'Some More of God\'s Greatest Mistakes', 'Oolon Colluphid', '17.99');
11. INSERT INTO books VALUES (3, 'Who Is This God Person Anyway?', 'Oolon Colluphid', '14.99');
12. Download this code: /code/php-cart-1.txt
Now that step is out of the way, let’s create our shopping cart.
Identify our requirements
The cart we are going to build should be pretty familiar to most internet users. It will provide a means of displaying a message on every page of the site (along the lines of “You have 5 items in your shopping cart”), which when clicked will take the customer to a list of the items in the cart; each item may be removed or have its quantity updated.
As all of our stock details are stored in the database, the only piece of information that we need to store about each customer is the id of each product they have added to their cart. To do this, we are going to use PHP’s built-in session handling capabilities.
Using sessions in PHP
PHP’s session handling is very easy to understand.
To ‘switch it on’, simply add session_start(); at the top of your code; you can then store values (or arrays) in session variables:
$_SESSION['name'] = 'Matthew'; $_SESSION['age'] = 31;
These $_SESSION variables will now be available to any PHP scripts on other pages (as long as you’ve included the session_start(); call first).
A short note on cookies
The default behaviour of PHP sessions is to store the session ID (a long string of numbers and letters that identifies you to the server) as a cookie on your computer; however, even if you have cookies disabled this functionality will still work – PHP will instead append the session ID to each link on the site (in the form ‘mypage.php?PHPSESSID=’) so that it can continue to accurately track visitors from page to page.
Creating the cart
We will store the contents of the shopping cart as a comma-separated list of product ids in a session named (unsurprisingly) ‘cart’ – for example, a cart containing “1,1,3,1,2” has four items; three of product #1, and one each of products #2 and #3.
Firstly, let’s create the code to display the “You have X items…” message on every page:
1. function writeShoppingCart() {
2. $cart = $_SESSION['cart'];
3. if (!$cart) {
4. return '
You have no items in your shopping cart
';5. } else {
6. // Parse the cart session variable
7. $items = explode(',',$cart);
8. $s = (count($items) > 1) ? 's':'';
9. return '
You have '.count($items).' item'.$s.' in your shopping cart
';10. }
11. }
12.
13. Download this code: /code/php-cart-2.txt
This function first gets the value of the ‘cart’ session variable into a local variable, mainly to save on typing. If the cart is empty, we return an appropriate message; if not, we use the explode() function to create an array of all the products in the cart, and then count() them and display the result (the $s variable is there to make plurals display correctly).
Now we can display the correct message anywhere on the site:
echo writeShoppingCart();
I hope that made sense; let’s move on to displaying the contents of the cart itself.
Show me the money
The shopping cart page itself (cart.php) can be arrived at in a couple of ways. The user may have clicked on the link created by the writeShoppingCart() function above; or, they may have clicked an ‘Add to cart’ link on a product page.
If it was the latter, we need to intercept that click and update our cart contents before displaying the new list of products – simple enough, as all we need to do is append the id of the clicked product to the ‘cart’ session variable. Our product links are going to look like this:
Add to cart
Don’t worry about the ‘action=add’ bit, we’ll get to that later. The id can now be extracted from $_GET[‘id’] and added to our cart:
1. $cart = $_SESSION['cart'];
2. if ($cart) {
3. $cart .= ','.$_GET['id'];
4. } else {
5. $cart = $_GET['id'];
6. }
7. $_SESSION['cart'] = $cart;
8. Download this code: /code/php-cart-3.txt
Now, on to the contents of our cart!
Multiple items, one product
As in our example above, it is entirely possible that a customer might have more than one of a certain product in their cart. As we don’t want to list duplicate items when we display the contents, we need to figure out a way to combine any of the same product into one entry (with a corresponding quantity attached).
1. $cart = $_SESSION['cart'];
2. if ($cart) {
3. $items = explode(',',$cart);
4. $contents = array();
5. foreach ($items as $item) {
6. $contents[$item] = (isset($contents[$item])) ? $contents[$item] + 1 : 1;
7. }
8. Download this code: /code/php-cart-4.txt
This time, after exploding the list of product ids, we have iterated through them to create a new array named $contents, which consists of key=>value pairs where the key is the product id and the value is the quantity of that product in the shopping cart. So to take our example above, a cart containing “1,1,3,1,2” would become an array where ‘1’=>3, ‘2’=>1, ‘3’=>1.
Now that we have an accurate count of unique products, let’s query the product database for each one and output its details into a table:
1. $total = 0;
2. $output[] = '
| Remove | ';'.$title.' by '.$author.' | ';£'.$price.' | ';'; | £'.($price * $qty).' | ';
18. $output[] = '
Grand total: £'.$total.'
';19.
20. Download this code: /code/php-cart-5.txt
(*Note*: I’m using a PHP class to handle my database connections, so your code may need to be slightly different).
Pretty simple stuff – we iterate through the new $contents array and query the database for each product id. Then we output the relevant details for each product; title, author and price, and at the bottom we show the grand total for the order. For each item, we’ve also included a link to remove the item from the cart, a textbox containing the current quantity of that item, and a total price (obviously this will only differ from the base price if the quantity is not 1).
The reason I’m using $output[] = ... is that I am buffering the output into an array to print to the screen later.
So far so good – now how about removing products from the cart?
Deleting a product
As shown above, the link to delete a product from the cart follows the same format as the ‘add a product’ link:
Remove
Let’s expand on the code from earlier by adding a switch() statement to handle the different things that might happen to our cart:
1. $cart = $_SESSION['cart'];
2. $action = $_GET['action'];
3. switch ($action) {
4. case 'add':
5. if ($cart) {
6. $cart .= ','.$_GET['id'];
7. } else {
8. $cart = $_GET['id'];
9. }
10. break;
11. case 'delete':
12. if ($cart) {
13. $items = explode(',',$cart);
14. $newcart = '';
15. foreach ($items as $item) {
16. if ($_GET['id'] != $item) {
17. if ($newcart != '') {
18. $newcart .= ','.$item;
19. } else {
20. $newcart = $item;
21. }
22. }
23. }
24. $cart = $newcart;
25. }
26. break;
27. }
28. $_SESSION['cart'] = $cart;
29. Download this code: /code/php-cart-6.txt
The new ‘delete’ case iterates through the ‘cart’ session, looking for any product ids that AREN’T the one we’re deleting, and adding them to a temporary variable called $newcart. When it’s finished, it puts the revised cart contents back into $cart.
Updating a product
Lastly, we are going to allow customers to update the contents of their shopping cart by manually changing the value in the quantity box for each product.
To make this work, we’ll wrap the shopping cart table in a ';
21. Download this code: /code/php-cart-7.txt
Note that, even though the form uses the POST method, its action includes a GET variable, “action=update”. Again, we can expand our previous code to process any quantity updates:
1. case 'update':
2. if ($cart) {
3. $newcart = '';
4. foreach ($_POST as $key=>$value) {
5. if (stristr($key,'qty')) {
6. $id = str_replace('qty','',$key);
7. $items = ($newcart != '') ? explode(',',$newcart) : explode(',',$cart);
8. $newcart = '';
9. foreach ($items as $item) {
10. if ($id != $item) {
11. if ($newcart != '') {
12. $newcart .= ','.$item;
13. } else {
14. $newcart = $item;
15. }
16. }
17. }
18. for ($i=1;$i<=$value;$i++) {
19. if ($newcart != '') {
20. $newcart .= ','.$id;
21. } else {
22. $newcart = $id;
23. }
24. }
25. }
26. }
27. }
28. $cart = $newcart;
29. break;
30.
31. Download this code: /code/php-cart-8.txt
This looks quite complicated, but it’s fairly straightforward; we interrogate the contents of the $_POST array (which holds all our quantity values) and extract the relevant id and value pairs. For each product, we then delete all the existing instances of it, and re-insert the new quantity.
There are a number of ways this could have been done – for example, by counting the existing number of each product present in the cart and figuring out whether we needed to add or remove items – but this seemed the easiest way to process the quantity updates.
Summary
And that’s about it! A functional and easy shopping cart script – here’s the final function to display the contents of the cart:
1. function showCart() {
2. $cart = $_SESSION['cart'];
3. if ($cart) {
4. $items = explode(',',$cart);
5. $contents = array();
6. foreach ($items as $item) {
7. $contents[$item] = (isset($contents[$item])) ? $contents[$item] + 1 : 1;
8. }
9. $output[] = '';
29. } else {
30. $output[] = '
You shopping cart is empty.
';31. }
32. return join('',$output);
33. }
34. Download this code: /code/php-cart-9.txt
Note that if the cart is empty, a suitable message is displayed.
A working demo can be seen (excuse the lack of design!), or please feel free to download a .zip of all the files – any questions, comments or suggestions on how the code could be improved gratefully received.
Filed under: PHP, MySQL.
Technorati tags: php mysql php shopping cart
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Comments
Matthijs
1782 days ago
Nice article! A good explanation for how the basics of a shopping cart work. That’ll help us on our way. Thanks.
#1
Christian Montoya
1779 days ago
Awesome. I bookmarked this for later.
#2
Hamish Keith
1774 days ago
Very very good – prob the best i have seen on the web
#3
Andrew
1769 days ago
Thank you so much for this tutorial. It was exactly what I’d been looking for for some time. Great design as well. Beautifully done.
#4
Greg Hamilton
1769 days ago
First of all wicked article, very helpful. Whats the best way to attempt the checkout ? Thanks
#5
Matthew Pennell
1769 days ago
Greg: Funny you should ask that, as I wrote an article that kind of touches on the subject – it is specific to Textpattern, but there is a section on ‘Shopping Integration’ that covers using PayPal to handle payment.
As we’re doing the shoppng cart bit ourselves, we could use PayPal’s new API to simply send the payment details and receive back the response (or whatever other payment processor we’re using).
#6
Greg Hamilton
1769 days ago
Hey Matt thanks for the with the checkout help, quick question about the update function..when you try to update an id that isn’t qty1 it doesnt update…not sure if I messed up the demo file or not :( thanks
#7
Greg Hamilton
1769 days ago
Sorry Matt I mean if you have, lets say two products in yer cart and you try to update the top one it doesnt, but the bottom one will. I think it does it in the demo as well….thanks bud
#8
Matthew Pennell
1768 days ago
Thanks, Greg – I’ve fixed the problem and updated the demo and .zip.
#9
Greg Hamilton
1766 days ago
Hey again Matt
Quick question about quantities, is ti possible to add a function that also allows the user to add quantities inside the product view before adding to cart. Thanks bud
#10
Matthew Pennell
1766 days ago
It would be very easy, Greg, although I don’t have time to do it right now – perhaps a later expansion, unless you want to add it in and publish your changes?
#11
Greg Hamilton
1766 days ago
Ya I’m gonna give it a go. I’ll publish when I get it all set to go.
#12
Andrew
1764 days ago
Hi,
Thanks for the tutorial!
i have changed the cart.php page a little. on the cart.php page, if the user clicks re-fresh, an item is added to the the cart as the ID ifor the product is stored in the querystring. its easily fixed.
Just a heads up for some.
Once again thanks for the demo!
#13
Viktor
1761 days ago
Great tutorial. Most tutorials takes too many steps at the same time so you only end up comfused, but this is vert easy to follow and understand.
#14
hidayat
1744 days ago
Good job boss
it’s nice tutorial ,too nice
#15
Franco
1743 days ago
Hi Matthew,
I test your script
but when i add to cart
this is message page:
Please check quantities…
You shopping cart is empty
I don’t see any product choice.
Can you help me?
Regards and happy New year
Franco
#16
Matthew Pennell
1742 days ago
Hi Franco – I’d need a bit more information to work out what might be wrong; the first thing to try though would be to echo the $id and $cart variables as the code progresses through the ‘add’ routine to see what is happening.
#17
The Illumidigerati
1735 days ago
Matt, does this cart form allow enough security for actual business transactions in the form of moneyorder/personal check? I’ll be webmastering my girlfriends home business and starting out neither of us are really keen on dealing with credit or any online payment ventures, i.e. paypal. Is there a reason for anything more secure when moneyorders/personal checks are the only payment methods since only user information will be logged, not CC info or bank account info?
#18
Matthew Pennell
1735 days ago
This cart script doesn’t handle any kind of payment; it is only for keeping track of what is in the shopping cart.
#19
dreamer85
1734 days ago
good tutorial well done
if it explaines how to display image with the products will be greate tutorial
take care
#20
Momotaro
1725 days ago
Excellent tutorial.
I’d like to know how to display the result in a Form that could then be saved to .csv file server-side? Ultimately, even send me an email when order Form was submited. The tutorials I’ve come across in past were too full of tech-speak that I couldn’t understand.
#21
Aneurin
1720 days ago
Thank You for the tutorial…
i was wondering if i could add product option to this shopping cart..eg. same item(same product id) but different options (size,colour)...i would appreciate some ideas…thanks in advance…
#22
Matthew Pennell
1720 days ago
Aneurin: Yes, that’s certainly an option; the project that I developed this cart code for does just that.
I used certain characters to split the product that was added to the cart, so to take your example of something with a certain size and colour, I would store the sizes and colours in their own tables in the database, then add products in the format “123c6s3”, which would translate as “Product #123, colour #6, size #3”.
The show-cart page would then lookup that colour and size from the table as part of the SQL statement and display the correct description of the product.
#23
Matthew Pennell
1720 days ago
Momotaro: Sending an email when the order is submitted would be pretty simple � the PHP mail() function covers that in detail.
#24
Aneurin
1719 days ago
Thank You very much…...
#25
momotaro
1717 days ago
Thanks for the link
#26
junwei
1709 days ago
nice! It help me alot, u mind adding add to cart and login function . thank
#27
Cormac
1708 days ago
are there anyother api’s that could be intergrated fairly easily with this shopping cart other than PayPal’s ?
#28
Matthew Pennell
1708 days ago
Cormac: There are quite a few online payment mechanisms that are as easy to integrate with as PayPal. WorldPay is probably the next best known one, but there are plenty around.
#29
Matt Cooper
1702 days ago
Nice code, and I very much like your website too, very fresh design. One disappointment (only a small one!) is that you haven’t provided further code for a checkout…is this on the cards? Good luck…
#30
Tan
1700 days ago
Great Demo, the best on the web!
I have one problem, same as franco above, I select add item and it displays check quantities on the cart page, with no items passed through. I have had a look over every page to no avail, would it be a function issue? It passes the id through the url but does not display it.
#31
James
1695 days ago
Hi Matt,
I’m new to all this and am pulling my hair out! – it just won’t work for me – getting messages such as:
Query failed: Unknown column ‘Array’ in ‘where clause’ SQL: SELECT * FROM book WHERE id = Array
or…
Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result
or…
Warning: mysql_num_rows(): supplied argument is not a valid MySQL
Where am I going wrong – from the other comments it seems to be pretty easy so it must be something I’m doing wrong!
Thanks for any help – very frstrated at the moment!
James
#32
Matthew Pennell
1695 days ago
James: That sounds as if the id is not being passed through in the querystring correctly. Check that you have populated the database correctly and have configured your database connection information properly.
#33
tan
1694 days ago
Just me again, why would it not display in the cart. Please note above note.
#34
Matthew Pennell
1694 days ago
Tan: It sounds as if the id variable in the querystring is not being picked up by the code (php-cart-3 in the code above) and added to the cart.
You could try adding a loop through all the items in the GET collection:
foreach ($_GET as $key => $value) {
echo $key . � contains � . $value . '
';
}
That will list everything all the variables in the querystring; if nothing is there, it may be that you�ve changed the form method to �post� instead of �get�? Or possibly you're using a very old version of PHP that doesn't support $_GET - you could try the above code with $HTTP_GET_VARS instead; if that works you'll have to change all instances of $_GET to $HTTP_GET_VARS (or upgrade to a host supporting a more modern version of PHP!)
#35
CHiNo4ReaL
1692 days ago
Nice tutorial, I’m gonna use it, but I have a question, is it possible to create catogory’s,
#36
Matthew Pennell
1692 days ago
Chino: Do you mean in the products listings, or in the cart session variable?
It depends how your database is set up whether you’d need any additional work to cope with categories.
#37
G
1692 days ago
Hello,
I have installed your cart on my website, but I have a problem. When I navigate between cart.php and index.php it appears this error message:
“Warning: session_start(): Cannot send session cache limiter – headers already sent (output started at ….global.inc.php:9) in cart.php on line 9”
“Warning: session_start(): Cannot send session cache limiter – headers already sent ”...
Can you please help me to solve it out?
Regards,
G.
#38
CHiNo4ReaL
1691 days ago
@Matthew
Yes, because i’m creating a webshop, with carparts, so there are a few catorgies, like exterior, frontbumpers, rims etc.
#39
CHiNo4ReaL
1691 days ago
Oh and another question, How can I finish the order?
#40
Matthew Pennell
1691 days ago
G: The session_start() command has to appear in the code before any output has been sent to the browser. As your error says, there is output being sent at line 9 of global.inc.php – you must have changed the source files, as my originals only have database connection variables in that file.
#41
Matthew Pennell
1691 days ago
Chino: Bear in mind that the id of the product that is held in the cart doesn’t have to include any reference to the category it is in.
You just have to alter the products database to include a category field; you can then use that when listing products, but just use the product id to hold it in the cart.
To finish the order, you’re going to have to decide what you want to do with it – either have it saved to a database, emailed to you, or processed by an online payment processor like PayPal. That’s beyond the scope of this tutorial, though.
#42
CHiNo4ReaL
1690 days ago
Ok, Do you have an example for the catorgyfield in the database?
#43
jatty5
1690 days ago
Hi all, I am new to this php and am trying to buid a shopping cart for my business myself. I have installed easyphp which has given me apache mysql and php, and am trying to work through this tutorial which I think is excellent for somebody like me a total novice! I have managed to create the database succesfully by copy the complete script and putting it through phpmyadmin. I tried to download the complete zip files, but where do i put them and how on earth do i set the database connection files up. Please help as I am getting alittle lost. I have also downloaded each script but agian where does it go, i know it would be in the WWW directory of my easyphp folder. Please help
#44
Matthew Pennell
1689 days ago
Chino: Just add a category field into your database using whatever MySQL admin tool you’re using.
#45
Matthew Pennell
1689 days ago
jatty5: If you have downloaded the zip you don’t need the individual scripts; just unpack the zip file to a folder under your www directory (e.g. “cart”). The database connection settings are in inc/global.inc.php if you need to change them, but if you’re running it locally the settings should be fine.
Then visit http://localhost/cart/ and it should all be working (you may have to start the PHP and MySQL services, depending on the package you are using).
#46
jatty5
1689 days ago
Hi Mathew, thanks for your swift reply, i have done what you said but still get the following reply:
I take it it has something to do with the database i created the database under phpmyadmin and called the database wtchproject and then run your script under that which created your tables under this database.
What do i change in the gobal file and is it possible for you to show where i can make those changes if possible.
Notice: Could not select database in c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php on line 80
Warning: session_start(): Cannot send session cookie – headers already sent by (output started at c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php:80) in c:\program files\easyphp1-8\www\cart-demo\index.php on line 9
Warning: session_start(): Cannot send session cache limiter – headers already sent (output started at c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php:80) in c:\program files\easyphp1-8\www\cart-demo\index.php on line 9
Your Shopping Cart
Notice: Undefined index: cart in c:\program files\easyphp1-8\www\cart-demo\inc\functions.inc.php on line 3
You have no items in your shopping cart
Books In Our Store
Notice: Query failed: No database selected SQL: SELECT * FROM books ORDER BY id in c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php on line 109
Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php on line 151
Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in c:\program files\easyphp1-8\www\cart-demo\inc\mysql.class.php on line 167
#47
ScopAL
1689 days ago
Notice: Undefined index: cart in z:\home\cart\www\inc\functions.inc.php on line 3
You have no items in your shopping cart
:((((
#48
CHiNo4ReaL
1689 days ago
Jatty5
I think that you have selected the wrong database, your database is called wtchprojec, but in the script its selecting books
#49
Matthew Pennell
1689 days ago
jatty5: I would suggest that if you’re trying to learn to use PHP/MySQL, it would be a good idea to learn all about creating database connections, but here is how to fix your problem:
In global.inc.php, you have four variables that are used to create the database connection:
$host = ‘localhost’;
$user = ‘root’;
$pass = ‘’;
$name = ‘’;
These correspond to your host name (usually ‘localhost’), the username and password you are using, and the name of your database.
So in your case, just change the last line to $name=’wtchproject’; and the database connection class object will then be pointing at your database.
#50
CHiNo4ReaL
1687 days ago
If I want the order mailed to me, how can I do that?
I have tried to do that, but i cant find any good ones, can u help me?
#51
Matthew Pennell
1687 days ago
I suppose you’d have to build in some data capture for the customer’s details, and then use mail() to send everything.
I’m not building the whole site for you, though..! ;)
#52
CHiNo4ReaL
1686 days ago
ok, thanks anyway
#53
Greg Hamilton
1684 days ago
Hey again Matt, what are your feelings on using cookies instead of sessions to remember the items that are in the shopping cart, do you think its necessary at all ?
#54
Matthew Pennell
1684 days ago
Greg: The benefit would obviously be that you would be able to leave the site and come back to the same basket; an approach using both sessions and cookies would probably be a good idea (with a fairly short expiration period).
#55
Juilius
1683 days ago
Hi I am having problems with the cart.php, whenever I hit the refresh button it adds another quantity to the cart? Any ideas?
Oh by the way, great, great example!
#56
Matthew Pennell
1682 days ago
Juilius: Yes, refreshing the page will add another item to the cart due to its use of the querystring ($_GET collection) to handle addition.
You can get around it by adding an extra session variable and storing the last item added and the time it was added, then checking against that to see if it is a repeated entry within a certain timeframe.
#57
Steven
1657 days ago
I’ll be messing around with this on XAMPP soon! I’m a bit of a PHP beginner but I thinks it’s important to dive in at the deep end!
#58
Steven
1657 days ago
I’ll be messing around with this on XAMPP soon! I’m a bit of a PHP beginner but I thinks it’s important to dive in at the deep end!
PS. Edited to ask, does a shopping cart system like this have to be bolted onto a dynamic website or can I add it to static product pages?
#59
Matthew Pennell
1657 days ago
Steven: I’m not sure how you’d use it with static pages, as it relies on a database of product details – I suppose you could copy your static data into the database, but if you’re doing that you may as well be using the database to output your product info as well!
#60
Fred
1641 days ago
I’m just curious, since this code connect to the db and all. Is this vulnerable to sql injection at all?
Can users modify the input variables or the session cookie to inject special characters that could cause buffer overflow in the SQL sequence?
I don’ recall seeing anywhere that inputs are scrubbed, but I could be wrong or the way the code is written, input scrubbing might be a non-issue.
Any confirmation on this?
#61
Matthew Pennell
1640 days ago
Fred: You are correct that if you wanted to use this in a commercial setting it would be a good idea to add some validation of the session data when it is read to output the contents of the cart. This could be as simple as using preg_match to check that the ID of the product is numeric.
#62
Fred
1640 days ago
This was some amazingly great cart code which gave me a good jump on what I wanted to create. Thanks Matt.
I did add some basic sanitization code to keep the db safe from SQL injects. You can take from the following.
I added a sanitization function and then called it on certain variable inputs used in the cart program:
function sanitize_system_string($string, $min=’’, $max=’’) {
$pattern = ’/(;|\||`|>| $max)))
return FALSE;
return $string;
}
// these occur in various places
sanitize_system_string($_GET[‘id’],1,50)
$cart = sanitize_system_string($_SESSION[‘cart’]);
$action = sanitize_system_string($_GET[‘action’],1,50);
// assigned right underneath the update switch foreach loop
$key = sanitize_system_string($key,1,50);
#63
Alex
1640 days ago
Thanx for the code Fred very helpful…
#64
Fred
1639 days ago
Sorry the sanitize_system_string function got partially truncated by the comment submit form. The other examples of variable sanitization remained in tact though.
Anyway, folks can get the point. Find a sanitization function, insert it in the functions php document and then employ it throughout the cart code as needed.
I identified several good places in the last post :)
I love this cart code matt provided! It has provided me the basis to do some wonders with it!
#65
Ella
1638 days ago
Hi There,
I am fairly new to php etc and am trying to do a shopping cart as part of my final project for my degree. I am getting an error when I click the add to cart link it goes through to the cart page but has the following error:
Parse error: parse error in c:\LocalUser\fashuti\public_html\cart.php on line 174
it is erroring on the last line of code on the page which is obciously not the problem. I have adapted the code on your size so that i can distinguish by id, size and colour. My id’s are both letter and charactger based. I can understand all of the code apart from one line which confuses me and I wonder if it could relate to that?
It seems you are comparing qty which is created here to the id?
foreach ($contents as $id=>$qty) {
I wondered if this could be my problem?
I will post my cart code below:
Hi There,
I am fairly new to php etc and am trying to do a shopping cart as part of my final project for my degree. I am getting an error when I click the add to cart link it goes through to the cart page but has the following error:
Parse error: parse error in c:\LocalUser\fashuti\public_html\cart.php on line 174
it is erroring on the last line of code on the page which is obciously not the problem. I have adapted the code on your size so that i can distinguish by id, size and colour. My id’s are both letter and charactger based. I can understand all of the code apart from one line which confuses me and I wonder if it could relate to that?
It seems you are comparing qty which is created here to the id?
foreach ($contents as $id=>$qty) {
I wondered if this could be my problem?
I will post my cart code below:
$total = 0;
$output[] = ‘’;
$conn=odbc_connect(‘danum_fashu’,’’,’’);
foreach ($contents as $id=>$qty) {
$sql = ‘SELECT * FROM products, product_line WHERE products.product_id = ’.$id.’ AND products.product_id = product_line.product_id AND product_line.product_size= ’.$sz.’ AND product_line.product_colour = ’.$col;
$rs=odbc_exec($conn,$sql);
$pid=odbc_result($rs,”product_line.product_id”);
$size=odbc_result($rs,”product_line.product_size”);
$name=odbc_result($rs,”products.product_name”);
$colour=odbc_result($rs,”product_line.product_colour”);
$cost=odbc_result($rs,”products.product_costprice”);
$endcost = number_format($cost * 2.6, 2, ’.’, ’,’);
$output[] = ‘’;
$output[] = ‘’.$pid.’ by ’.$name.’’;
$output[] = ‘’.$size.’ ’.$colour.’’;
$output[] = ’£’.$endcost.’’;
$output[] = ‘’;
$output[] = ’£’.($endcost * $qty).’’;
$output[] = ‘Remove’;
$total += $endcost * $qty;
$output[] = ‘’;
}
$output[] = ‘’;
$output[] = ‘Grand total: £’.$total.’’;
odbc_close($conn);
Any help would be gratefully recieved
2010年10月9日星期六
SimpleXML介绍
SimpleXML提供了一种简单，直观的方法来处理XML。它只有一个单一类型的类，三个函数和六个方法。
使用SimpleXML
SimpleXMLElement 类是这个扩展中所有操作的核心类。可以用new关键字直接创建这种类，或是使用simplexml_load_file()或 simplexml_load_string()函数返回这种类。本文将使用清单7-1的XML文档来说明如何使用SimpleXML，将此文档命名为 sml.xml。
清单7-1 sml.xml
1.
2. 3. "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd">
4.
5.
6.SimpleXML in PHP 5
7.
8.Rob
9.Richards
10.
11.
12.2005
13.Rob Richards
14.
15.
16.
17.Using SimpleXML
18.An example DOM Tree using DocBook.
19.
20.
21.Accessing Elements
22.Elements are accessed as properties
23.
24. 25. 26. $data = '
27.content ';
28. $sxe = simplexml_load_string($data);
29. var_dump($sxe);
30. ?>
31. ]]>
32.
33.
34.
创建一个SimpleXMLElement对象
使用new关键字创建
1. $xml = "Content
2. $sxe = new SimpleXMLElement($xml);//SimpleXMLElement Object ( [node1] => Content )
使用simplexml_load_string()创建
1. $xml = "Content
2. $sxe = simplexml_load_string($xml);//SimpleXMLElement Object ( [node1] => Content )
如何选择这两种创建SimpleXMLElement的方法呢？simplexml_load_string()提供了更多的函数，比如控制解析选项的能力。如果不需要这些额外的函数的话就可以凭个人爱好选择一种方法。
使用simplexml_load_file()从一个URI创建
1. $sxe = simplexml_load_file("filename.xml");
simplexml_load_string()和simplexml_load_file()都有一个必需的参数和可选的参数。从PHP5.1开始simplexml_load_file()多了一个用来控制解析行为的第三个参数。
1. /* Prototype for PHP 5.0 */
2. simplexml_load_file(string data [, string class_name])
3. /* Prototype for PHP 5.1 */
4. simplexml_load_file(string data [, string class_name [, int options]])
保存XML数据
与DOM扩展一样，SimpleXML也提供了一个用来输出XML内容的方法asXML()。可以用这个方法以字符串或文件形式输出这个文档或文档中的某个节点。
1. $xml = "content
2. $sxe = new SimpleXMLElement($xml);
3. print $sxe->asXML();
4. $sxe->asXML('test.xml');
输出：
1.
2.content
访问元素节点
在SimpleXML中，可以直接通过元素的名称来访问特定的元素。
访问元素
当一个文档被载入SimpleXML时，文档被看成是一个SimpleXML对象，文档中的所有元素都被看成是该对象的属性。
1. 2. $book = simplexml_load_file('sxml.xml');
3. /* Access the bookinfo child element of the book element */
4. $bookinfo = $book->bookinfo;
5. /* Access the title child element from the bookinfo element */
6. $title = $bookinfo->title;
7. ?>
如果使用DOM来访问title，代码如下
1. $dom = new DOMDocument();
2. $dom->load('sxml.xml');
3. $book = $dom->documentElement;
4. foreach($book->childNodes as $node) {
5. if ($node->nodeName == "bookinfo") {
6. foreach($node->childNodes as $child) {
7. if ($child->nodeName == "title") {
8. $node = $child;
9. break 2;
10. }
11. }
12. }
13. }
14. if ($node) {
15. $title = $node;
16. }
显然SimpleXML对的起它的名字。
访问内容
1. 2. $book = simplexml_load_file('sxml.xml');
3. $bookinfo = $book->bookinfo;
4. $title = $bookinfo->title;
5. /* Object examined with var_dump */
6. var_dump($title);
7. /* Using print with element containing text-only content */
8. print "Title: ".$title."\n";
9. $author = $bookinfo->author;
10. /* Object examined with var_dump */
11. var_dump($author);
12. /* Using print with element containing child elements */
13. print "Author: ".$author."\n";
14. ?>
这段代码检查了两个SimpleXMLElement对象，$author和$title。两者的区别是$author元素有包含子元素而$title元素只包含一个文本节点。
输出如下：
object(SimpleXMLElement)#4 (1) {
[0]=>
string(18) “SimpleXML in PHP 5″
}
Title: SimpleXML in PHP 5
object(SimpleXMLElement)#6 (2) {
[”firstname”]=>
string(3) “Rob”
[”surname”]=>
string(8) “Richards”
}
Author:
检查输出结果可以发现，$title是一个包含有文本内容的SimpleXMLElement对象，索引0表示元素的文本内容，当打印$title时，文本内容将以字符串形式返回。
$author元素有两个子元素，从输出结果可以看出，这些子元素被看成SimpleXMLElement对象的属性，这些属性的值是它们对应的节点包含的内容。用print输出$author时，输出结果是空格和换行符。
如果一个元素无子元素，只包含文本内容，那么可以将此元素所对应的SimpleXMLElement对象视为一个字符串来使用，有些情况下，为了获得以字符串形式返回文本内容，必须执行类型转换操作：
1. $titlecontent = (string) $title;
有子元素的元素所对应的SimpleXMLElement对象将返回该对象直属的文本节点，而不是任一子元素的内容。如果用print输出$author，将得到一个27字符长度，包含空格和换行符的字符。 Neither of the child elements,firstname or surname, nor their content is returned in the string.
为了理解最后一点，可以运行一些下面这段代码：
1. $doc = new SimpleXMLElement('somesubtext thing ');
2. print $doc;
使用迭代对象
SimpleXMLElement 对象在大多数情况下是可迭代的，可以用这个特性来访问文档中多个元素名一样的节点，如清单7-1中的para元素。在使用元素名作为属性来访问一个元素时，SimpleXMLElement对象不是一个单一节点的存取器，它实际上是作为属性访问的元素名节点的集合。直接利用元素名作为属性访问实际上访问访问这个集合中的第一个元素。
看下这段代码
1. $book = simplexml_load_file('sxml.xml');
2. $para = $book->chapter->para;
3. print $para."\n";
4. foreach($para AS $node) {
5. print $node."\n";
6. }
这段代码中，$para变量就是para元素的集合，实际上包含了两个元素。如果直接访问$para的话实际上是访问第一个para元素，利用迭代可以看出 $para所包含的内容是两个元素。其中CDATA节点被看做是纯文本的内容，其中包含的空格和换行符都会被如实输出。
用迭代的方式来访问所有的元素显然不太实际，有时候我们希望访问结果集中的某个特定的元素，这时可以使用从0开始的索引来访问这个结果集，例如：
1. $book = simplexml_load_file('sxml.xml');
2. $para = $book->chapter->para[1];
3. print "Content: ".$para."\n";
4. foreach($para AS $node) {
5. print "Iter Content: ".$node."\n";
6. }
运行这段代码会发现foreach循环失效了，这是因为SimpleXML知道你只是在寻找结果集中某个特定的元素，这种情况下对象是不可迭代的。
Caution:使用索引方式访问一个SimpleXMLElement对象会返回一个不可以迭代的对象，因为它是一个单一的元素而不是一个元素集。
访问未知元素
在不知道XML文档的结构的情况下可以利用SimpleXML中的children()方法来返回一个可以迭代方式访问的某个元素的所有子元素的SimpleXML对象。如：
1. $book = simplexml_load_file('sxml.xml');
2. $author = $book->bookinfo->author;
3. $children = $author->children();
4. foreach($children AS $child) {
5. print $child."\n";
6. }
上述代码用children()方法返回了author节点下的所有子元素，然后用foreach循环输出。也可以使用索引方式访问返回的子元素，如echo $children[1];。
理解PHP对象函数
SimpleXMLElement对象的属性是动态的，因为这些属性是由对象实例决定的，而不是由类本身决定的。在PHP中，可以利用get_object_vars()函数来返回某个对象的所有属性，返回的结果是一个包含属性和值的数组，如：
1. $props = get_object_vars($author);
2. foreach ($props AS $name=>$value) {
3. print $name.": ".$value."\n";
4. }
输出：
firstname: Rob
surname: Richards
这段代码访问的子元素都只包含文本内容，所以返回的数组只包含属性名和值，对于一个包含许多子节点的元素，返回的结果稍微复杂点：
1. $props = get_object_vars($book->bookinfo);
2. var_dump($props);
输出:
array(3) {
[”title”]=>
string(18) “SimpleXML in PHP 5″
[”author”]=>
object(SimpleXMLElement)#4 (2) {
[”firstname”]=>
string(3) “Rob”
[”surname”]=>
string(8) “Richards”
}
[”copyright”]=>
object(SimpleXMLElement)#5 (2) {
[”year”]=>
string(4) “2005″
[”holder”]=>
string(12) “Rob Richards”
}
}
使用DOM互操作
另一种访问未知元素的方法是使用DOM，可以将一个节点导入DOM扩展，然后使用DOM的属性和方法来处理。
1. $book = simplexml_load_file('sxml.xml');
2. $author = $book->bookinfo->author;
3. $children = $author->children();
4. foreach($children AS $child) {
5. /* Import node into DOM, and get nodeName */
6. $element = dom_import_simplexml($child);
7. $name = $element->nodeName;
8. print $name.": ".$child."\n";
9. }
将节点导入DOM扩展时并没有创建一个节点的副本(copy)，而是直接访问导入的节点（JIMMY注：这个概念很重要）。
修改内容
利用SimpleXML修改元素内容非常方便，你可以改变或移除树中的某个元素，但是不能直接在树中添加一个元素。要添加一个元素，可以使用DOM的互操作性：
1. $xml = "content
2. $sxe = new SimpleXMLElement($xml);
3. $dom = dom_import_simplexml($sxe);
4. $dom->appendChild(new DOMElement("node2", "content2"));
5. print $sxe->asXML();
输出：
1.
2.content content2
编辑文本内容
可以利用SimpleXML的属性赋值方法来直接编辑一个元素的内容，要主意的是如果文档中有多个元素名一样的元素，如果没有使用索引来指定要编辑哪个元素时PHP将发出一个警告。如：
1. $book = simplexml_load_file('sxml.xml');
2. /* Modify an unspecified para element where multiple para elements exist */
3. $book->chapter->para = "Removed CDATA";
输出：
Warning: main() [/phpmanual/function.main.html]: Cannot assign to an array of nodes
(duplicate subnodes or attr detected)
必须给para指定索引告诉程序你要编辑哪个元素：
1. $book = simplexml_load_file('sxml.xml');
2. $book->chapter->para[1] = "Removed CDATA";
3. print $book->chapter->asXML();
输出：
1.
2.Acessing Elements
3.Elements are accessed as properties
4.Removed CDATA
5.
这样，第二个para元素的内容被改为Removed CDATA。如果要编辑一个在文档中唯一存在的元素可不必指定索引，直接修改。如修改title：
1. $book = simplexml_load_file('sxml.xml');
2. $book->chapter->title = "New Title";
3. $book->chapter->para[1] = "Removed CDATA";
4. print $book->chapter->asXML();
输出：
1.
2.New Title
3.Elements are accessed as properties
4.Removed CDATA
5.
强烈建议使用索引来编辑元素，除非你对文档的结果非常确定。使用索引来编辑title元素会比较安全，如$book->chapter->title[0] = “New Title”;这行代码用索引[0]指定要编辑第一个title。
编辑有子树的元素
1. $book = simplexml_load_file('sxml.xml');
2. $cholder = $book->bookinfo->copyright->holder;
3. print $cholder->asXML()."\n";
4. $book->bookinfo = "No Book Info";
5. print $book->bookinfo->asXML()."\n";
6. print $cholder->asXML()."\n";
输出：
1.Rob Richards
2.No Book Info
3. Warning: SimpleXMLElement::asXML() [/phpmanual/function.asXML.html]: Node no
4. longer exists in N:\CVS Projects\php5\Debug_TS\booksxe.php on line 7
这段代码中，首先将文档中的holder元素赋值给$cholder变量，然后打印该变量。bookinfo元素包含有title，author和 copyright子树，它的内容被字符串No Book Info代替，从bookinfo的输出结果可以看出，它的子树被清空并且被字符串代替了。接着试图再次打印$cholder变量的XML内容，程序输出一个警告，这个变量依然是一个SimpleXMLElement对象，但它所属的节点在bookinfo元素改变时已经被破坏了。
另一种情况。将bookinfo元素中的子元素用字符串 代替。
1. $book = simplexml_load_file('sxml.xml');
2. $book->bookinfo = "SimpleXML in PHP 5 ";
3. print $book->bookinfo->asXML()."\n";
如果你认为上述代码将bookinfo中的内容清空后再给bookinfo创建了一个子节点title，那么你错了。输出结果是
SimpleXML in PHP 5
实际上bookinfo元素的子元素都被移除了，但是新赋值的XML数据被转义成文本内容，而不是一个新的子元素。
如果想用一个子树代替另一个子树，可以利用DOM扩展：
1. $book = simplexml_load_file('sxml.xml');
2. $bookinfo = dom_import_simplexml($book->bookinfo);
3. /* 移除bookinfo元素下的所有子元素*/
4. while ($bookinfo->firstChild) {
5. $bookinfo->removeChild($bookinfo->firstChild);
6. }
7. $bookinfo->appendChild(new DOMElement("title", "SimpleXML in PHP 5"));
8. print $book->bookinfo->asXML()."\n";
输出结果：
1.
2.SimpleXML in PHP 5
3.
移除元素
可以用PHP内置函数unset()来将一个元素从树中移除。unset()的参数必须是一个SimpleXMLElement，用属性方法来访问要移除的元素。例如，从chapter节点移除title元素：
1. $book = simplexml_load_file('sxml.xml');
2. $book->chapter->para[1] = "Removed CDATA";
3. unset($book->chapter->title);
4. print $book->chapter->asXML();
上述代码执行后，chapter的结构为：
1.
2.
3.Elements are accessed as properties
4.Removed CDATA
5.
将这个结果与下面代码执行的结果想比较：
1. $book = simplexml_load_file('sxml.xml');
2. $book->chapter->para[1] = "Removed CDATA";
3. $title = $book->chapter->title;
4. unset($title);
5. print $book->chapter->asXML();
输出结果
1.
2.Acessing Elements
3.Elements are accessed as properties
4.Removed CDATA
5.
title元素没有被移除，unset函数只对$title变量作用并没有将title元素从树中移除。
在移除一个元素时必须注意，用索引来指定的特定元素不会被移除：
1. $book = simplexml_load_file('sxml.xml');
2. $book->chapter->para[1] = "Removed CDATA";
3. unset($book->chapter->title[0]);
4. print $book->chapter->asXML();
输出：
1.
2.Acessing Elements
3.Elements are accessed as properties
4.Removed CDATA
5.
如果要移除所有的para元素时可以利用下面代码：
1. $book = simplexml_load_file('sxml.xml');
2. unset($book->chapter->para);
3. print $book->chapter->asXML();
输出：
1.
2.Acessing Elements
3.
4.
5.
问题是如果你只想移除其中的一个para元素时要怎么办。这时可以再次用到DOM扩展：
1. $book = simplexml_load_file('sxml.xml');
2. $chapter = dom_import_simplexml($book->chapter);
3. $node = $chapter->lastChild;
4. while($node) {
5. if ($node->nodeName == "para") {
6. $chapter->removeChild($node);
7. $node = NULL;
8. break;
9. }
10. $node = $node->previousSibling;
11. }
12. print $book->chapter->asXML();
输出：
1.
2.Acessing Elements
3.Elements are accessed as properties
4.
5.
所幸的是PHP5.2开始已经支持删除用索引指定的元素了：
1. $book = simplexml_load_file('sxml.xml');
2. unset($book->chapter->para[1]);
3. print $book->chapter->asXML();
访问属性
读取属性
下面的代码输出了book元素中的lang属性
1. $book = simplexml_load_file('sxml.xml');
2. print $book['lang'];
访问用索引指定的元素的属性：
1. $book = simplexml_load_file('sxml.xml');
2. print $book->chapter[0]['id'];
在不知道属性名的情况下可以用attributes()方法来输出属性：
1. $book = simplexml_load_file('sxml.xml');
2. foreach($book->chapter->attributes() AS $attribute) {
3. print $attribute."\n";
4. }
如果要获得位置的属性名，可以使用DOM扩展：
1. $book = simplexml_load_file('sxml.xml');
2. foreach($book->chapter->attributes() AS $attribute) {
3. $att = dom_import_simplexml($attribute);
4. print $att->nodeName."\n";
5. print $attribute."\n";
6. }
修改属性
修改属性的值跟修改元素的值一样，直接对其赋值就可以了：
1. $book = simplexml_load_file('sxml.xml');
2. $book['lang'] = "es";
3. print $book['lang'];
添加一个属性也很简单，如果对一个不存在的属性名进行赋值就给元素创建一个新属性
1. $book = simplexml_load_file('sxml.xml');
2. $book->bookinfo->author->firstname["prefix"] = "Mr.";
3. print $book->bookinfo->author->asXML();
输出：
1.
2.Rob
3.Richards
4.
移除属性
移除属性也用到unset()函数:
1. $book = simplexml_load_file('sxml.xml');
2. $book->bookinfo->author->firstname["prefix"] = "Mr.";
3. print $book->bookinfo->author->firstname->asXML()."\n\n";
4. unset($book->bookinfo->author->firstname["prefix"]);
5. print $book->bookinfo->author->firstname->asXML();
输出：
1.Rob
2.
3.Rob
扩展SimpleXMLElement类
1. class mySXE extends SimpleXMLElement {
2. function appendChild($name, $content) {
3. $dom = dom_import_simplexml($this);
4. $dom->appendChild($dom->ownerDocument->createElement($name, $content));
5. }
6. }
当实例化扩展的类时，文档的每个节点对象的类型都是扩展类的类型。
1. $sxe = new mySXE("
2. $sxe->node1->appendChild("node2", "content");
3. print $sxe->asXML();
输出：
1.
2.content
使用new方法可以用来处理字符串类型的XML，如果XML保存在一个文件中，那么可以将扩展的类名作为第二个参数传给simplexml_load_string或simplexml_load_file
1. $sxe = simplexml_load_string("
2. $sxe->node1->appendChild("node2", "content");
3. print $sxe->asXML();
输出结果与用new关键字输出的结果一样。
在SimpleXML中使用命名空间
将清单7-1的内容改为
1.
2.
3.
4.SimpleXML in PHP 5
5.
6.Rob
7.Richards
8.
9.
10.2005
11.Rob Richards
12.
13.
14.
如果试图用普通的方法来访问元素或属性，你会分析这并不可行，例如：
1. $book = simplexml_load_file('sxmlns.xml');
2. print $book["lang"]."\n";
3. print $book->bookinfo->title."\n";
输出的结果是两行空白。
在访问命名空间节点前，必须使用children()和attributes()方法。这两个方法不仅可以在没有指定参数的时候使用，也可以在指定一个 URI命名空间作为参数使用。如果一个SimleXMLElement对象是从这两个方法返回的，那么你就可以像普通的元素和属性一样访问命名空间下的元素和属性：
1. $book = simplexml_load_file('sxmlns.xml');
2. /* 返回 http://www.example.com/ns2 命名空间下的所有属性 */
3. $bookatts = $book->attributes("http://www.example.com/ns2");
4. print $bookatts["lang"]."\n";
5. /* 返回 http://www.example.com/ns1 命名空间下的所有元素*/
6. $bookns = $book->children("http://www.example.com/ns1");
7. $bookinfo = $bookns->bookinfo;
8. /* 重置命名空间来访问非命名空间的元素 */
9. $nonsbkinfo = $bookinfo->children();
10. print $nonsbkinfo->title."\n";
children ()和attributes()方法可以被看做是过滤器，如果没有参数或者传递一个NULL作为参数，这两个方法将返回非命名空间下的元素或属性；否则将返回特定命名空间下的元素或属性。在重置之前，命名空间仍然起作用并且被子节点继承。例如，使用$bookinfo被设置为命名空间 http://www.example.com/ns1的对象，可以使用 print $bookinfo->author->firstname来但因author中的firstname元素。所有的元素都在命名空间下，因此你在创建$bookinfo对象时不必一直使用children()设置命名空间。
使用SimpleXML
SimpleXMLElement 类是这个扩展中所有操作的核心类。可以用new关键字直接创建这种类，或是使用simplexml_load_file()或 simplexml_load_string()函数返回这种类。本文将使用清单7-1的XML文档来说明如何使用SimpleXML，将此文档命名为 sml.xml。
清单7-1 sml.xml
1.
2. 3. "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd">
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24. 25. 26. $data = '
27.
28. $sxe = simplexml_load_string($data);
29. var_dump($sxe);
30. ?>
31. ]]>
32.
33.
34.
创建一个SimpleXMLElement对象
使用new关键字创建
1. $xml = "
2. $sxe = new SimpleXMLElement($xml);//SimpleXMLElement Object ( [node1] => Content )
使用simplexml_load_string()创建
1. $xml = "
2. $sxe = simplexml_load_string($xml);//SimpleXMLElement Object ( [node1] => Content )
如何选择这两种创建SimpleXMLElement的方法呢？simplexml_load_string()提供了更多的函数，比如控制解析选项的能力。如果不需要这些额外的函数的话就可以凭个人爱好选择一种方法。
使用simplexml_load_file()从一个URI创建
1. $sxe = simplexml_load_file("filename.xml");
simplexml_load_string()和simplexml_load_file()都有一个必需的参数和可选的参数。从PHP5.1开始simplexml_load_file()多了一个用来控制解析行为的第三个参数。
1. /* Prototype for PHP 5.0 */
2. simplexml_load_file(string data [, string class_name])
3. /* Prototype for PHP 5.1 */
4. simplexml_load_file(string data [, string class_name [, int options]])
保存XML数据
与DOM扩展一样，SimpleXML也提供了一个用来输出XML内容的方法asXML()。可以用这个方法以字符串或文件形式输出这个文档或文档中的某个节点。
1. $xml = "
2. $sxe = new SimpleXMLElement($xml);
3. print $sxe->asXML();
4. $sxe->asXML('test.xml');
输出：
1.
2.
访问元素节点
在SimpleXML中，可以直接通过元素的名称来访问特定的元素。
访问元素
当一个文档被载入SimpleXML时，文档被看成是一个SimpleXML对象，文档中的所有元素都被看成是该对象的属性。
1. 2. $book = simplexml_load_file('sxml.xml');
3. /* Access the bookinfo child element of the book element */
4. $bookinfo = $book->bookinfo;
5. /* Access the title child element from the bookinfo element */
6. $title = $bookinfo->title;
7. ?>
如果使用DOM来访问title，代码如下
1. $dom = new DOMDocument();
2. $dom->load('sxml.xml');
3. $book = $dom->documentElement;
4. foreach($book->childNodes as $node) {
5. if ($node->nodeName == "bookinfo") {
6. foreach($node->childNodes as $child) {
7. if ($child->nodeName == "title") {
8. $node = $child;
9. break 2;
10. }
11. }
12. }
13. }
14. if ($node) {
15. $title = $node;
16. }
显然SimpleXML对的起它的名字。
访问内容
1. 2. $book = simplexml_load_file('sxml.xml');
3. $bookinfo = $book->bookinfo;
4. $title = $bookinfo->title;
5. /* Object examined with var_dump */
6. var_dump($title);
7. /* Using print with element containing text-only content */
8. print "Title: ".$title."\n";
9. $author = $bookinfo->author;
10. /* Object examined with var_dump */
11. var_dump($author);
12. /* Using print with element containing child elements */
13. print "Author: ".$author."\n";
14. ?>
这段代码检查了两个SimpleXMLElement对象，$author和$title。两者的区别是$author元素有包含子元素而$title元素只包含一个文本节点。
输出如下：
object(SimpleXMLElement)#4 (1) {
[0]=>
string(18) “SimpleXML in PHP 5″
}
Title: SimpleXML in PHP 5
object(SimpleXMLElement)#6 (2) {
[”firstname”]=>
string(3) “Rob”
[”surname”]=>
string(8) “Richards”
}
Author:
检查输出结果可以发现，$title是一个包含有文本内容的SimpleXMLElement对象，索引0表示元素的文本内容，当打印$title时，文本内容将以字符串形式返回。
$author元素有两个子元素，从输出结果可以看出，这些子元素被看成SimpleXMLElement对象的属性，这些属性的值是它们对应的节点包含的内容。用print输出$author时，输出结果是空格和换行符。
如果一个元素无子元素，只包含文本内容，那么可以将此元素所对应的SimpleXMLElement对象视为一个字符串来使用，有些情况下，为了获得以字符串形式返回文本内容，必须执行类型转换操作：
1. $titlecontent = (string) $title;
有子元素的元素所对应的SimpleXMLElement对象将返回该对象直属的文本节点，而不是任一子元素的内容。如果用print输出$author，将得到一个27字符长度，包含空格和换行符的字符。 Neither of the child elements,firstname or surname, nor their content is returned in the string.
为了理解最后一点，可以运行一些下面这段代码：
1. $doc = new SimpleXMLElement('
2. print $doc;
使用迭代对象
SimpleXMLElement 对象在大多数情况下是可迭代的，可以用这个特性来访问文档中多个元素名一样的节点，如清单7-1中的para元素。在使用元素名作为属性来访问一个元素时，SimpleXMLElement对象不是一个单一节点的存取器，它实际上是作为属性访问的元素名节点的集合。直接利用元素名作为属性访问实际上访问访问这个集合中的第一个元素。
看下这段代码
1. $book = simplexml_load_file('sxml.xml');
2. $para = $book->chapter->para;
3. print $para."\n";
4. foreach($para AS $node) {
5. print $node."\n";
6. }
这段代码中，$para变量就是para元素的集合，实际上包含了两个元素。如果直接访问$para的话实际上是访问第一个para元素，利用迭代可以看出 $para所包含的内容是两个元素。其中CDATA节点被看做是纯文本的内容，其中包含的空格和换行符都会被如实输出。
用迭代的方式来访问所有的元素显然不太实际，有时候我们希望访问结果集中的某个特定的元素，这时可以使用从0开始的索引来访问这个结果集，例如：
1. $book = simplexml_load_file('sxml.xml');
2. $para = $book->chapter->para[1];
3. print "Content: ".$para."\n";
4. foreach($para AS $node) {
5. print "Iter Content: ".$node."\n";
6. }
运行这段代码会发现foreach循环失效了，这是因为SimpleXML知道你只是在寻找结果集中某个特定的元素，这种情况下对象是不可迭代的。
Caution:使用索引方式访问一个SimpleXMLElement对象会返回一个不可以迭代的对象，因为它是一个单一的元素而不是一个元素集。
访问未知元素
在不知道XML文档的结构的情况下可以利用SimpleXML中的children()方法来返回一个可以迭代方式访问的某个元素的所有子元素的SimpleXML对象。如：
1. $book = simplexml_load_file('sxml.xml');
2. $author = $book->bookinfo->author;
3. $children = $author->children();
4. foreach($children AS $child) {
5. print $child."\n";
6. }
上述代码用children()方法返回了author节点下的所有子元素，然后用foreach循环输出。也可以使用索引方式访问返回的子元素，如echo $children[1];。
理解PHP对象函数
SimpleXMLElement对象的属性是动态的，因为这些属性是由对象实例决定的，而不是由类本身决定的。在PHP中，可以利用get_object_vars()函数来返回某个对象的所有属性，返回的结果是一个包含属性和值的数组，如：
1. $props = get_object_vars($author);
2. foreach ($props AS $name=>$value) {
3. print $name.": ".$value."\n";
4. }
输出：
firstname: Rob
surname: Richards
这段代码访问的子元素都只包含文本内容，所以返回的数组只包含属性名和值，对于一个包含许多子节点的元素，返回的结果稍微复杂点：
1. $props = get_object_vars($book->bookinfo);
2. var_dump($props);
输出:
array(3) {
[”title”]=>
string(18) “SimpleXML in PHP 5″
[”author”]=>
object(SimpleXMLElement)#4 (2) {
[”firstname”]=>
string(3) “Rob”
[”surname”]=>
string(8) “Richards”
}
[”copyright”]=>
object(SimpleXMLElement)#5 (2) {
[”year”]=>
string(4) “2005″
[”holder”]=>
string(12) “Rob Richards”
}
}
使用DOM互操作
另一种访问未知元素的方法是使用DOM，可以将一个节点导入DOM扩展，然后使用DOM的属性和方法来处理。
1. $book = simplexml_load_file('sxml.xml');
2. $author = $book->bookinfo->author;
3. $children = $author->children();
4. foreach($children AS $child) {
5. /* Import node into DOM, and get nodeName */
6. $element = dom_import_simplexml($child);
7. $name = $element->nodeName;
8. print $name.": ".$child."\n";
9. }
将节点导入DOM扩展时并没有创建一个节点的副本(copy)，而是直接访问导入的节点（JIMMY注：这个概念很重要）。
修改内容
利用SimpleXML修改元素内容非常方便，你可以改变或移除树中的某个元素，但是不能直接在树中添加一个元素。要添加一个元素，可以使用DOM的互操作性：
1. $xml = "
2. $sxe = new SimpleXMLElement($xml);
3. $dom = dom_import_simplexml($sxe);
4. $dom->appendChild(new DOMElement("node2", "content2"));
5. print $sxe->asXML();
输出：
1.
2.
编辑文本内容
可以利用SimpleXML的属性赋值方法来直接编辑一个元素的内容，要主意的是如果文档中有多个元素名一样的元素，如果没有使用索引来指定要编辑哪个元素时PHP将发出一个警告。如：
1. $book = simplexml_load_file('sxml.xml');
2. /* Modify an unspecified para element where multiple para elements exist */
3. $book->chapter->para = "Removed CDATA";
输出：
Warning: main() [/phpmanual/function.main.html]: Cannot assign to an array of nodes
(duplicate subnodes or attr detected)
必须给para指定索引告诉程序你要编辑哪个元素：
1. $book = simplexml_load_file('sxml.xml');
2. $book->chapter->para[1] = "Removed CDATA";
3. print $book->chapter->asXML();
输出：
1.
2.
3.
4.
5.
这样，第二个para元素的内容被改为Removed CDATA。如果要编辑一个在文档中唯一存在的元素可不必指定索引，直接修改。如修改title：
1. $book = simplexml_load_file('sxml.xml');
2. $book->chapter->title = "New Title";
3. $book->chapter->para[1] = "Removed CDATA";
4. print $book->chapter->asXML();
输出：
1.
2.
3.
4.
5.
强烈建议使用索引来编辑元素，除非你对文档的结果非常确定。使用索引来编辑title元素会比较安全，如$book->chapter->title[0] = “New Title”;这行代码用索引[0]指定要编辑第一个title。
编辑有子树的元素
1. $book = simplexml_load_file('sxml.xml');
2. $cholder = $book->bookinfo->copyright->holder;
3. print $cholder->asXML()."\n";
4. $book->bookinfo = "No Book Info";
5. print $book->bookinfo->asXML()."\n";
6. print $cholder->asXML()."\n";
输出：
1.
2.
3. Warning: SimpleXMLElement::asXML() [/phpmanual/function.asXML.html]: Node no
4. longer exists in N:\CVS Projects\php5\Debug_TS\booksxe.php on line 7
这段代码中，首先将文档中的holder元素赋值给$cholder变量，然后打印该变量。bookinfo元素包含有title，author和 copyright子树，它的内容被字符串No Book Info代替，从bookinfo的输出结果可以看出，它的子树被清空并且被字符串代替了。接着试图再次打印$cholder变量的XML内容，程序输出一个警告，这个变量依然是一个SimpleXMLElement对象，但它所属的节点在bookinfo元素改变时已经被破坏了。
另一种情况。将bookinfo元素中的子元素用字符串 代替。
1. $book = simplexml_load_file('sxml.xml');
2. $book->bookinfo = "
3. print $book->bookinfo->asXML()."\n";
如果你认为上述代码将bookinfo中的内容清空后再给bookinfo创建了一个子节点title，那么你错了。输出结果是
实际上bookinfo元素的子元素都被移除了，但是新赋值的XML数据被转义成文本内容，而不是一个新的子元素。
如果想用一个子树代替另一个子树，可以利用DOM扩展：
1. $book = simplexml_load_file('sxml.xml');
2. $bookinfo = dom_import_simplexml($book->bookinfo);
3. /* 移除bookinfo元素下的所有子元素*/
4. while ($bookinfo->firstChild) {
5. $bookinfo->removeChild($bookinfo->firstChild);
6. }
7. $bookinfo->appendChild(new DOMElement("title", "SimpleXML in PHP 5"));
8. print $book->bookinfo->asXML()."\n";
输出结果：
1.
2.
3.
移除元素
可以用PHP内置函数unset()来将一个元素从树中移除。unset()的参数必须是一个SimpleXMLElement，用属性方法来访问要移除的元素。例如，从chapter节点移除title元素：
1. $book = simplexml_load_file('sxml.xml');
2. $book->chapter->para[1] = "Removed CDATA";
3. unset($book->chapter->title);
4. print $book->chapter->asXML();
上述代码执行后，chapter的结构为：
1.
2.
3.
4.
5.
将这个结果与下面代码执行的结果想比较：
1. $book = simplexml_load_file('sxml.xml');
2. $book->chapter->para[1] = "Removed CDATA";
3. $title = $book->chapter->title;
4. unset($title);
5. print $book->chapter->asXML();
输出结果
1.
2.
3.
4.
5.
title元素没有被移除，unset函数只对$title变量作用并没有将title元素从树中移除。
在移除一个元素时必须注意，用索引来指定的特定元素不会被移除：
1. $book = simplexml_load_file('sxml.xml');
2. $book->chapter->para[1] = "Removed CDATA";
3. unset($book->chapter->title[0]);
4. print $book->chapter->asXML();
输出：
1.
2.
3.
4.
5.
如果要移除所有的para元素时可以利用下面代码：
1. $book = simplexml_load_file('sxml.xml');
2. unset($book->chapter->para);
3. print $book->chapter->asXML();
输出：
1.
2.
3.
4.
5.
问题是如果你只想移除其中的一个para元素时要怎么办。这时可以再次用到DOM扩展：
1. $book = simplexml_load_file('sxml.xml');
2. $chapter = dom_import_simplexml($book->chapter);
3. $node = $chapter->lastChild;
4. while($node) {
5. if ($node->nodeName == "para") {
6. $chapter->removeChild($node);
7. $node = NULL;
8. break;
9. }
10. $node = $node->previousSibling;
11. }
12. print $book->chapter->asXML();
输出：
1.
2.
3.
4.
5.
所幸的是PHP5.2开始已经支持删除用索引指定的元素了：
1. $book = simplexml_load_file('sxml.xml');
2. unset($book->chapter->para[1]);
3. print $book->chapter->asXML();
访问属性
读取属性
下面的代码输出了book元素中的lang属性
1. $book = simplexml_load_file('sxml.xml');
2. print $book['lang'];
访问用索引指定的元素的属性：
1. $book = simplexml_load_file('sxml.xml');
2. print $book->chapter[0]['id'];
在不知道属性名的情况下可以用attributes()方法来输出属性：
1. $book = simplexml_load_file('sxml.xml');
2. foreach($book->chapter->attributes() AS $attribute) {
3. print $attribute."\n";
4. }
如果要获得位置的属性名，可以使用DOM扩展：
1. $book = simplexml_load_file('sxml.xml');
2. foreach($book->chapter->attributes() AS $attribute) {
3. $att = dom_import_simplexml($attribute);
4. print $att->nodeName."\n";
5. print $attribute."\n";
6. }
修改属性
修改属性的值跟修改元素的值一样，直接对其赋值就可以了：
1. $book = simplexml_load_file('sxml.xml');
2. $book['lang'] = "es";
3. print $book['lang'];
添加一个属性也很简单，如果对一个不存在的属性名进行赋值就给元素创建一个新属性
1. $book = simplexml_load_file('sxml.xml');
2. $book->bookinfo->author->firstname["prefix"] = "Mr.";
3. print $book->bookinfo->author->asXML();
输出：
1.
2.
3.
4.
移除属性
移除属性也用到unset()函数:
1. $book = simplexml_load_file('sxml.xml');
2. $book->bookinfo->author->firstname["prefix"] = "Mr.";
3. print $book->bookinfo->author->firstname->asXML()."\n\n";
4. unset($book->bookinfo->author->firstname["prefix"]);
5. print $book->bookinfo->author->firstname->asXML();
输出：
1.
2.
3.
扩展SimpleXMLElement类
1. class mySXE extends SimpleXMLElement {
2. function appendChild($name, $content) {
3. $dom = dom_import_simplexml($this);
4. $dom->appendChild($dom->ownerDocument->createElement($name, $content));
5. }
6. }
当实例化扩展的类时，文档的每个节点对象的类型都是扩展类的类型。
1. $sxe = new mySXE("
2. $sxe->node1->appendChild("node2", "content");
3. print $sxe->asXML();
输出：
1.
2.
使用new方法可以用来处理字符串类型的XML，如果XML保存在一个文件中，那么可以将扩展的类名作为第二个参数传给simplexml_load_string或simplexml_load_file
1. $sxe = simplexml_load_string("
2. $sxe->node1->appendChild("node2", "content");
3. print $sxe->asXML();
输出结果与用new关键字输出的结果一样。
在SimpleXML中使用命名空间
将清单7-1的内容改为
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
如果试图用普通的方法来访问元素或属性，你会分析这并不可行，例如：
1. $book = simplexml_load_file('sxmlns.xml');
2. print $book["lang"]."\n";
3. print $book->bookinfo->title."\n";
输出的结果是两行空白。
在访问命名空间节点前，必须使用children()和attributes()方法。这两个方法不仅可以在没有指定参数的时候使用，也可以在指定一个 URI命名空间作为参数使用。如果一个SimleXMLElement对象是从这两个方法返回的，那么你就可以像普通的元素和属性一样访问命名空间下的元素和属性：
1. $book = simplexml_load_file('sxmlns.xml');
2. /* 返回 http://www.example.com/ns2 命名空间下的所有属性 */
3. $bookatts = $book->attributes("http://www.example.com/ns2");
4. print $bookatts["lang"]."\n";
5. /* 返回 http://www.example.com/ns1 命名空间下的所有元素*/
6. $bookns = $book->children("http://www.example.com/ns1");
7. $bookinfo = $bookns->bookinfo;
8. /* 重置命名空间来访问非命名空间的元素 */
9. $nonsbkinfo = $bookinfo->children();
10. print $nonsbkinfo->title."\n";
children ()和attributes()方法可以被看做是过滤器，如果没有参数或者传递一个NULL作为参数，这两个方法将返回非命名空间下的元素或属性；否则将返回特定命名空间下的元素或属性。在重置之前，命名空间仍然起作用并且被子节点继承。例如，使用$bookinfo被设置为命名空间 http://www.example.com/ns1的对象，可以使用 print $bookinfo->author->firstname来但因author中的firstname元素。所有的元素都在命名空间下，因此你在创建$bookinfo对象时不必一直使用children()设置命名空间。
SimpleXML php操作xml的简单入门
DOM是Document Object Model文档对象模型的缩写。根据W3C DOM规范（http://www.w3.org/DOM/），DOM是一种与浏览器，平台，语言无关的接口，使得你可以访问页面其他的标准组件。
说到对xml文件的操作，简单的入门的话无非是: 读取文件，写文件，修改文件 首先说读取文件，我们可以使用两种方法，一种是dom方式，一种是php提供的SimpleXMLElement对象。 我的xml文件中的内容如下： 名字叫做test1.xml $xmlstr = 'test1.xml'; //加载xml文件(load a xml file) //$xml = simplexml_load_file($xmlstr); //这也是一种简单可行的方法 //the third parameter means the first parameter is url or not $xml = new SimpleXMLElement($xmlstr,NULL,TRUE); //以属性的方式读取 //echo $xml->book[0]->title; //循环度读取元素 foreach ($xml->book as $book ){ //echo $book->plot." "; } //修改文本节点信息 $xml->book[0]->define = "self define!"; //插入节点 $mybook = $xml->addChild('book'); $mybook->addChild('title','Anna'); $mybook->addChild('plot','About Anna'); $mybook->addChild('define','added by me!'); echo $xml->asXML(); //输出xml文件内容 代码很清晰，不用更多解释了。下面的是使用dom对象读取的方法: $dom = new DOMDocument('1.0'); $books = $dom->getElementsByTagName('book'); //注意这里获取的类型是DOMNodelist $book = $books->item(0); //这里获取的类型是DOMNode $title = $book->getElementsByTagName('title'); echo $title->item（0）->nodeValue; //输出节点信息 这里有点难理解，关键是DOMNodelist和DOMNode这两种类型。 nodelist就像一个数组，是我们用getElementsByTagName获取到的，它具有item方法，item后面可以跟上index来指明是访问那个node，有点类似与数组但是用法完全不一样。node的话，具有nodeValue这个属性，可是使用它来访问node的具体内容。 对于nodelist，一般都倾向与使用迭代来便利，用法如下: foreach($books as $book){ //$books是nodelist类型的，$book是node类型的 //具体操作 } 读文件完成了，下面是写文件: //创建一个dom对象 $dom = new DOMDocument('1.0'); //创建根节点 $books = $dom->appendChild($dom->createElement('books')); //创建子节点 $book = $books->appendChild($dom->createElement('book')); //创建子节点 $title = $book->appendChild($dom->createElement('title')); //写入文本内容 $title->appendChild($dom->createTextNode('Great American Novel')); //格式化输出 $dom->formatOutput = true; //保存xml到文件 $dom -> save('test1.xml'); // save as file 最后是修改文件,其实也很简单，打开以后读取node的值，修改，然后保存就可以了。 //读取根节点 $root = $dom->getElementsByTagName('books'); //创建一个book节点 $mybook = $dom->createElement('book'); //添加到根节点 $root->item(0)->appendChild($mybook); //创建title节点 $title = $dom->createElement('title'); //向title节点写入文本内容 $title->appendChild($dom->createTextNode('The deviche code')); //修改文本内容 $title->nodeValue='my novel'; //添加到book节点 $mybook->appendChild($title); //保存xml文件 $dom->save($xml_path); 修改文本的时候有两种方法，个人感觉第二种直接写nodeValue更好一些。 掌握了这三种操作，简单的xml操作基本就没有问题了。 这里有所有你想要的： DOMNodelist讲解: http://www.phpchina.com/manual/php/function.dom-domnodelist-item.html phpsimplexml官方帮助文档: http://us3.php.net/manual/en/book.simplexml.php |
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