sessions and Objects

[dkode]

I am using sessions to pass the main object from one page to another in a shopping cart script. The main object is $cart

Here is some code:
?
session_start();
session_register('cart');

include("cart_class.php");
include("db.php");

if (!is_object($cart)) {
$cart = new Cart;
$test = "yadda yadda";
}

if (!$func) {
// Get all items from the database and put into an Array
$query = "SELECT id, pName FROM hal_item";
$qresult = mysql_db_query($database, $query, $connection) or die ("Error in query: $query . " . mysql_error());
while($row = mysql_fetch_row($qresult)) {
$id = $row[0];
$pname = $row[1];
$products_arr[$id] = $pname;
}

// Show all Items
foreach ($products_arr as $id => $product) {
	$url_product = urlencode($product);
	echo "Product: <a href='$PHP_SELF?sid=$SID&func=add&id=$id&product=$url_product'>$product</a><br>\n";
}
echo $cart;

}

if ($func == 'add') {
// Add function
// add("ID", NUM);
// Adds NUM to cart for ID
$result = $cart->add("$id", "$product", 1);
echo $result;
}

When I try this it gives me this error:

Fatal error: The script tried to execute a method or access a property of an incomplete object. Please ensure that the class definition cart of the object you are trying to operate on was loaded before the session was started in /xxx/xxxx/products.php on line 43

Does anyone know why it is doing this? Is it possible to pass objects through sessions? And if i do it like this, will each user that creates a new $cart object have a unique cart?

[knickerlas]

Why don't you try doing what the warning told you?

Please ensure that the class definition cart of the object you are trying to operate on was loaded before the session was started

include("cart_class.php");
session_start();

Hmmm...? 😉

Nick

[dkode]

Figured it out....

When passing objects in query strings or sessions you must serialize and unserialize like so:

session_start();
session_register('cartref');

When the script starts (near header)
$cart = unserialize($cartref);

Once you are done doing what you have to:

$cartref = serialize($cart);

You must do it in $cartref because if not the integrity of the object will not be valid.

[dkode]

you were right :o)

Thanks.

[Anon]

I guess this means you can't use session.auto_start if you are going to store objects in the session.