array_key_exists() error

[ragrim]

Hi,

 

Im encountering this error when i add items to my cart, im using sessions to store my cart items in an array. this error only happens the first time i add something, then if i go clear my session it works and no errors.

 

Warning: array_key_exists() [function.array-key-exists]: The second argument should be either an array or an object in /home/byronhea/public_html/oos/mini-cart.php on line 18

 

Here is the line its refering to

 

 

	if(array_key_exists($pid, $_SESSION['cart']))

 

and here is the block of code it belongs to

 

	if(!isset($_SESSION)) 
{ 
session_start('cart');
}
// Process actions

$pid = $_POST['prodid'];
$q = $_POST['qty'];

if(array_key_exists($pid, $_SESSION['cart']))
{
	$_SESSION['cart'][$pid]=$_SESSION['cart'][$pid]+$q;	
}
ELSE
{
	$_SESSION['cart'][$pid]=$q;
}

 

Any help would be appreciated.

[psynor]

Can you var_dump your $_SESSION['cart']

[ragrim]

i made a change to my code and have not recieved any errors as yet, but its hard to tell if i fixed it as this error is random and doesnt happen all the time.

 

i changed it to

 

if(isset($_SESSION['cart'][$pid]))
{
$_SESSION['cart'][$pid]=$_SESSION['cart'][$pid]+$q;	
}
else
{
$_SESSION['cart'][$pid]=$q;
}

 

I was reading in the php manual that using isset may not be the right way to go about this but its the only way i could avoid the error as any other way seems to produce random errors.

 

Any help would be appreciated.

[xyph]

You have to check if the key exists and contains an array before using array_key_exists()

 

Alternately, you can simply use isset()

 

if( isset($_SESSION['cart'][$pid] ) {

    // etc.

}

 

This won't result in an error if ['cart'] doesn't exist, and is actually faster than array_key_exists()