将多个产品添加到购物车

Question

I have some problem with the logic and any help would be appreciated:

$total_add = $_POST['xTotalNumProduct'];

if(ISSET($_SESSION['cart']['CartTotalNum']) && $_SESSION['cart']['CartTotalNum'] > 0) {
    $CartTotalNum = $_SESSION['cart']['CartTotalNum'];
    $cart = $_SESSION['cart'];

    for ($i=1; $i<=$total_add; $i++) {

        for ($x=1; $x<=$CartTotalNum; $x++) {
            if ($cart['ItemId'.$x] == $_POST['xPdt'.$i.'Id']) { // this will only check the first key ie $cart['ItemId1]
                $cart['ItemQty'.$x] = $_POST['xPdt'.$i.'Qty'];
            }
            else {
                $CartTotalNum = $CartTotalNum + 1;
                $cart['ItemId'.$CartTotalNum] = $_POST['xPdt'.$i.'Id'];
                $cart['ItemQty'.$CartTotalNum] = $_POST['xPdt'.$i.'Qty'];
            }
        }
    }
    $cart['CartTotalNum'] = $CartTotalNum;

} else {
    $cart = array();
    for ($i=1; $i<=$total_add; $i++) {
        $cart['ItemId'.$i] = $_POST['xPdt'.$i.'Id'];
        $cart['ItemQty'.$i] = $_POST['xPdt'.$i.'Qty'];      
    }
    $cart['CartTotalNum'] = $total_add;
}

The problem with the above script is that it only checks the $cart['ItemId1] and if not equal it will add to cart without checking $cart['ItemId2], $cart['ItemId3] etc.

How can I fix that?

Answer 1

This is incredibly bad code:

            $cart['ItemQty'.$x] = $_POST['xPdt'.$i.'Qty'];
                          ^^^^^

Why build dynamic keys? You can use a multi-dimensional arrays quiet easily:

   $_SESSION['cart'][$itemID]['quantity'] = $_POST[...];

Keying your cart by the itemID allows all of the item's cart data to be kept in one place, instead of scattered everywhere.

And note that similar constructs can be used in your form field names, e.g.

<input type="text" name="foo[bar][baz][42]" ... >

would give you

$_REQUEST['foo']['bar']['baz'][42]

to work with when the form's submitted.