$_POST['num'] = 'abc'; include 'add_to_cart.php'; $this->expectOutputRegex('/Invalid quantity/');
<script> function addToCart(productId) // Get quantity from input let numInput = document.getElementById('qty-' + productId); let quantity = numInput ? numInput.value : 1; addcartphp num high quality
To add a high-quality "add to cart" feature in PHP, you typically use PHP Sessions to store item data persistently as a user browses. A robust addcart.php $_POST['num'] = 'abc'; include 'add_to_cart
// --- DATABASE LOOKUP (Prepared Statement) --- $pdo = getDbConnection(); $stmt = $pdo->prepare("SELECT id, name, price, stock_quantity FROM products WHERE id = ? AND status = 1"); $stmt->execute([$product_id]); $product = $stmt->fetch(PDO::FETCH_ASSOC); AND status = 1")
This uses FILTER_VALIDATE_INT (not intval() ), which distinguishes between 0 , null , and false . It rejects decimals, strings, and empty values explicitly.
For long-term carts that survive browser closures, consider storing cart items in a MySQL database linked to a user ID.