How to check against stock level variable when updating quantities in cart view

I am incorporating stock control into an eCart site and it's working fine when adding an item but I need to insert some checking code when the cart is updated if the quantity is changed. I need a steer as to where I should put any code. I could add a column to the cart items to hold the stock level so I can then compare that to the quantity in the cart, or I could do a query to check it, but I don't know where any of that code should go.

Can you point me in the right direction?

Many thanks

Jon

in the cart object, add a column for the available quantity, and save the available quantity in the add to cart button

you can then create a calculation in the cart object to force the quantity to be the available quantity is they try to order more than are available:

abs([Quantity] > [AvailableQuatity])?[Quantity] = [AvailableQuatity];''

Thanks Jason, that looks exactly what I need. Quick question, though. Where should I put that code snippet? I'm in the cart.php script which has the standard updatable cart displayed.

Cheers

Jon

create a new calculation in the cart object using the code snippet above.

the calculation code code snippet assumes the availbal quantity column is named AvailableQuatity

Thanks again Jason.

The snippet you've given was giving me the white screen so I've had a look in eCart1_PHP.php and found the two place where that is inserted and have manually edited them to show this:

if($itmObj->Quantity > $itmObj->StockLevel) {
$itmObj->Quantity = $itmObj->StockLevel;
}

(my column for stock is StockLevel)

and this is now working. However, it is screwing up the Cart Object dialogue so I would be keen to do it properly. Are you able to suggest what the problem could be?

Thanks again

Jon

What was the code originally? i would need to know what the code was before you edited it to be able to tell what was wrong.

Hi Jason

I put in what you gave me in this thread:

abs([Quantity] > [AvailableQuatity])?[Quantity] = [AvailableQuatity];''

I changed it to:

abs([Quantity] > [StockLevel])?[Quantity] = [StockLevel];''

and also tried:

abs([Quantity] > [StockLevel])?[Quantity] = [StockLevel]

and:

abs([Quantity] > [StockLevel])?[Quantity] = [StockLevel];

but always giving the white screen.

Hope that helps.

Cheers

Jon

I see, it shouldn't be a semi colon, but a full colon:
abs([Quantity] > [StockLevel])?[Quantity] = [StockLevel]:''