Posted by Joseph Melnick on 09/26/05 01:23

Crista Wrote:
"Christa Lee" <Ck.lee@telus.net> wrote in message
news:mHDZe.190667$wr.164531@clgrps12...
> Hi there,
> thanks for the response. It looks like it might work for me but will it
> work for a product where I need to store the size, colour and quantity?
> For example, what if someone orders a large blue sweater and then the same
> sweater except also in green and XL?
>
> Thanks,
> D
>
> "Geoff Berrow" <blthecat@ckdog.co.uk> wrote in message
> news:ouncj19u48ajg0n9eilkrtkps14ji8v1gf@4ax.com...
>>I noticed that Message-ID: <XJpZe.269622$HI.141531@edtnps84> from
>> Christa Lee contained the following:
>>
>>>If someone can tell me where I'm going wrong or if someone has an example
>>>shopping cart for a clothing web site, please HELP ME!
>>
>> The only thing you really need to store is the quantity and the product
>> id Everything else can come from the database. I've just done one
>> (literally, last week ) and I stored the price as well so that I could
>> have a running total. From an individual item page I have an add to
>> cart button and a text box to choose the quantity. The product id comes
>> from the URL. So when the form is submitted:
>>
>> session_start();
>> if(isset($_POST['qty'])){
>> $_SESSION['quantity'][$_GET['product_id']]=$_POST['qty'];
>> $_SESSION['price'][$_GET['product_id']=$_POST['price'];
>> }
>>
>> Then there is a link to a cart page which shows the contents of the cart
>> I need to create a query that will fetch back the relevant rows
>>
>>
>> foreach($_SESSION['quantity'] as $key=>$value)
>> {
>> $cartitems[]="product_id = $key";
>> }
>> $q=implode(" or ",$cartitems);
>> $sql="SELECT * FROM products where $q";
>> ...
>>
>>
>> I then loop through the results ans show the products. Each one has a
>> form with a text box showing the quantity, and two buttons, change and
>> delete. At the top of the file I have:
>>
>> if(isset($_POST['change'])){
>> $_SESSION['quantity'][$_POST[$prodkey]]=$_POST['qty'];
>>
>> }
>> if(isset($_POST['delete'])||$_POST['qty']<1){
>> unset($_SESSION['quantity'][$_POST[$prodkey]]);
>> }
>>
>> Then you just need a bit of code to do the calculations
>> $qty=0;
>> $total_cost=0;
>> foreach($_SESSION['quantity'] as $pid=>$no){
>> $qty=$qty+$no;
>> $total_cost=$total_cost+($no*$_SESSION['price'][$pid]);
>> }
>>
>> Obviously there is a bit more code than this, to check there is anything
>> in the cart for instance, but there you have the basics.
>>
>> This site is a work in progress, but you can check it out here
>> www.playhifi.com
>>
>>
>> --
>> Geoff Berrow 0110001001101100010000000110
>> 001101101011011001000110111101100111001011
>> 100110001101101111001011100111010101101011
>
>

A product with optional components (size,colour) can be handled a number of
ways.

If a person adds an optioned product to their cart you need to maintain the
option to product association.

When a person adds an optioned product to their cart in my ecommerce system
they are posting a dynamically generated form which contains the following
Keys and their values:
ACTION,ID, CODE, PRICE, NAME, DESCRIPTION, QUANTITY, COLOUR and SIZE.

First I check to see if the cleint has already added this product to their
cart.
If true do the options match
if yes then increment quantity with the number being added to the cart
else
add this product to the cart with is unique options (1, SW01, 10.00,
Sweater, A Fabulous Sweater, Size=L, Colour=Red)
else
add this product to the cart with is unique options (1, SW01, 10.00,
Sweater, A Fabulous Sweater, Size=L, Colour=Red)

Same logic for modifying quantities in the shopping cart.
if match code AND options
change quantity
if quantity requested is zero(0)
delete item from cart


in your case you have ID and QUANTITY so you need to pass OPTIONS as well
SIZE and COLOUR.

then:
Things to be handled:
1, option exists for product.
2, each option type for given product is satisfied.
(0 options none selected, 1 option type and 1 selection of type, 2 option
types and 2 selections one of each type)
3a, add to cart if unique product and options
3b, update cart if added product matches existing cart item

I do hope that I have given you some insight into the logic required to
allow products with options for your website. I could write a book on this
very topic especially ecommerce system processes with payment gateway
integrations.

Joseph Melnick
JM Web Consultants
Toronto, ON Canada

[Back to original message]