Changing Add to Cart Function

[jonathan_pohl]

I'm trying to change the function of the add to cart button so that rather than literally adding the number in the quantity box on the product page to the number of that product already in the cart, it overwrites this quantity. to understand why i want to do this you can check out the way i reworked my products page here:

http://www.sphotos.biz/store/index.p...th=1_2_3_59_60

Basically i had a bunch of pictures to sell with a bunch of different sizes available so i made the image name the category and added all the sizes as products under that category. Anyways, I want make it so when a user returns to the "product" page (usually from clicking the image in the shopping cart) the quantity boxes are filled with the number of items already in the cart and hitting the add to cart button overwrites the values in the cart.

Thanks!

[jonathan_pohl]

I finally had a chance to take a look at this myself. I'm looking specifically at the function that controlls adding multiple products to cart (since i altered my category listing page). To do this open shopping_cart.php in the includes\classes folder, then look for:

function actionMultipleAddProduct($goto, $parameters) {

Change the function so it reads as follows:

  function actionMultipleAddProduct($goto, $parameters) {
    global $messageStack;
    while ( list( $key, $val ) = each($_POST['products_id']) ) {
      if ($val > 0) {
        $prodId = $key;
        $qty = $val;
        $add_max = zen_get_products_quantity_order_max($prodId);
        //$cart_qty = $this->in_cart_mixed($prodId);
        $new_qty = $qty;
        if (($add_max == 1 and $cart_qty == 1)) {
          // do not add
          $adjust_max= 'true';
        } else {
          // adjust quantity if needed
          if (($new_qty > $add_max) and $add_max != 0) {
            $adjust_max= 'true';
            $new_qty = $add_max;
          }
          $this->add_cart($prodId, ($new_qty));
        }
        if ($adjust_max == 'true') {
          $messageStack->add_session('shopping_cart', ERROR_MAXIMUM_QTY . ' - ' . zen_get_products_name($prodId), 'caution');
        }
      }
    }
    zen_redirect(zen_href_link($goto, zen_get_all_get_params($parameters)));
  }

I'm now working on making the input boxes display the current cart quantity but that shouldn't be as difficult to track down.