php session problem

[korcian]

include("wfcart.php");

session_start();
if (!isset($SESSION['cart'])) {
$cart = new wfCart();
} else {
$cart = $SESSION['cart'];
}

$cart->add_item($itemid,$qty,$price,$info);

---

There is something missing because it's creating the sessions, but in the session file, there is no data.

Any ideas on this would be greatly appreciated!!!

[korcian]

please please please can someone help, i'm really struggling with this 🙁

[Installer]

What and where is the code that sets "$_SESSION['cart']"?

[korcian]

This line does that, doesn't it?

$cart->add_item($itemid,$qty,$price,$info);

Then I call the php?itemid=example

[Installer]

No, it doesn't. This, for example, would:

$_SESSION['cart'][] = array(($itemid,$qty,$price,$info);

would.

In your code you're assigning "$cart" to equal "$SESSION['cart']" which, according to your "if" clause, is not even set (no value). Also, if it is set, you assign it as a class instance. Presumably, in the couse of your script, you'll end up with both assignments being made. But you can't have it both ways. It looks to me like you're confusing several concepts ("$SESSION" variable, class object, "register_globals on", etc.) as all being the same thing.

[korcian]

that's what i tried a few days ago but i wasn't sure where to place it. I'm seriously trying my best to understand this?

This is wfcart.php, any ideas?

<?php

class wfCart {
	var $total = 0;
	var $itemcount = 0;
	var $items = array();
        var $itemprices = array();
	var $itemqtys = array();
        var $iteminfo = array();

function cart() {} // constructor function

function add_item($itemid,$qty=1,$price = FALSE, $info = FALSE)
{ // adds an item to cart
            if(!$price)
	{
	        $price = wf_get_price($itemid,$qty);
	}

            if(!$info)
	{
                    $info = wf_get_info($itemid);
	}

	if($this->itemqtys[$itemid] > 0)
            { // the item is already in the cart..
	  // so we'll just increase the quantity
		$this->itemqtys[$itemid] = $qty + $this->itemqtys[$itemid];
		$this->_update_total();
	} else {
		$this->items[]=$itemid;
		$this->itemqtys[$itemid] = $qty;
		$this->itemprices[$itemid] = $price;
		$this->iteminfo[$itemid] = $info;
	}
	$this->_update_total();
} // end of add_item


function _update_total()
{ // internal function to update the total in the cart
        $this->itemcount = 0;
	$this->total = 0;
            if(sizeof($this->items > 0))
	{
                    foreach($this->items as $item) {
                            $this->total = $this->total + ($this->itemprices[$item] * $this->itemqtys[$item]);
			$this->itemcount++;
		}
	}
} // end of update_total

}
?>

[Installer]

Look at it this way:

The information you want to maintain and carry from page to page, script to script, and all the way through checkout is: the customer, items he/she has ordered, and how many of each item. Tracking the customer is done by the session module itself via the SID (Session ID), so all you have to do for that is use 'session_start()" for each page. An item and how many of it should be added to "$SESSION['cart']" when the user clicks to order that item. So you could structure "$SESSION['cart']" like:

[CODE]$_SESSION['cart'][$item_number] => $item_quantity[/CODE]Meaning, when the user clicks to order an item, that item number is used as the index for the second array dimension, and its quantity as the value associated with that index. This is the information you need to persistently store in "_$SESSION", the information your "add_item()" method should add to "$_SESSION". The other stuff, such as item price, total price, item description, etc. can be either computed or retrieved from db "as-needed".

When the customer get to checkout, his "$_SESSION" may look like this:

[CODE]$_SESSION['cart'] => array([1066] => 2 
                       [0201] => 5
                       [0205] => 1)[/CODE](i.e., "Customer's cart contains 2 of item #1066, 5 of item #0201, and 1 of item #0205).

Then you can compute total cost, shipping weight, etc., and add customer shipping information, allocate order number, get payment, etc. Any of these that need to be carried through checkout page to page would be given their own indexes;

[CODE]$_SESSION['customer_name']     => 'Junior Johnson'

$SESSION['order_number'] => '12345'
$SESSION['total_order_price'] => ((2 $00.98) +
(5 $08.98) +
(1 * $98.98))
$_SESSION['payment method'] => 'Visa'
etc.[/CODE]hth

[korcian]

woah, thanks alot for the tutorial mate!!! I've read through it a few times and i'm going to try and get my scripts working tommorow.

Just a little question, if i have a variable which i need to be passed within the session, do i just put e.g.

$_SESSION['variable'] = $variable_name

and this carries over the variables right? I've tried putting it in the add_item function but didn't have any luck 🙁 I'll try again tommorow. But thanks loads for the help!!!!!!!!!!!!!!!!!!!