PHP Sessions shopping cart: update product if it's already id the session

Question

I have struggled to find a solution to a simple shopping cart with $_SESSION. I kept it very simple and this is my code right now

if ( Input::isPos         


        

Answer 1

$postedQuantity = intval($_POST['quantity']);
$postedProduct = $_POST['product'];
$postedSize = $_POST['size'];

$productId = $_POST['product'] . $_POST['size'];// concat the product name/Id and //the size form a new array-key.it will be unique.

if(empty($_SESSION)){
$_SESSION['cart_items'] = array();
}

if(empty($_SESSION['cart_items'])) {
    $_SESSION['cart_items'][$productId] = array('name'=> $_POST['product'],
                                            'quantity'=> intval($_POST['quantity']),
                                            'size'=>$_POST['size'],
                                 );
} elseif(!array_key_exists($productId,$_SESSION['cart_items'])) {
    $_SESSION['cart_items'][$productId] = array('name'=> $_POST['product'],
                                  'quantity'=> intval($_POST['quantity']),
                                  'size'=>$_POST['size'],
                                 );
}
else { 
   $_SESSION['cart_items'][$productId]['quantity'] += $postedQuantity;
}