Ajax shopping cart

Shopping carts play an important role in e-commerce websites. In this task, we will learn how to build a shopping cart with Ajax functionality to provide the best user experience. The result of this task will look like the following screenshot:

Getting ready

All we need for this task is the latest jQuery library and a sample .php file, ajax/shopping-cart.php.

This script will provide basic server functionality to retrieve and receive data:

<?php
if($_POST["productID"] && $_POST["action"]){
  $productID = $_POST["productID"];
  $action = $_POST["action"];
  switch($action){
    default:
        $result["status"] = "ERROR";
        $result["message"] = "Product has been added to the shopping cart.";
    break;
    case "add":
        // logic for adding a product to the shopping cart
        $result["status"] = "OK";
        $result["message"] = "Product has been added to the shopping cart.";
    break;
    case "delete":
        // logic for removing a product from...