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PHP and MySQL Shopping Cart Tutorial – Using SESSIONS To Store Cart Data

shopping-cart-in-php-sessions

Previously, we learned how to build a Shopping Cart with PHP & MySQL where we used a database to store cart items. Today, we will learn another version of it. We will use PHP session variables to store cart items.

This tutorial have the following contents:

1.0 Overview
2.0 Tutorial Output Preview
3.0 File Structure

4.0 Prepare the database
4.1 Database design
4.2 Create a database
4.3 Create “products” table
4.4 Create “categories” table
4.5 Download sample data and images
4.6 Extract and import data
4.7 Database connection file
4.8 Output

5.0 Create the layout files
5.1 Create header layout file
5.2 Create footer layout file
5.3 Create navigation layout file
5.4 Create Custom CSS file
5.5 Output

6.0 Display Products
6.1 Create product page
6.2 Include PHP Classes
6.3 Create "product" object
6.4 Create "product image" object
6.5 Connect to the database
6.6 Initialize action and pagination
6.7 Display messages based on action
6.8 Request data from the database
6.9 Add "read" and "count" methods
6.10 Template to display products
6.11 Add "readFirst()" method
6.12 Make "add to cart" button work
6.13 Create pagination file
6.14 Output

7.0 How to add to cart?
7.1 Create add_to_cart.php
7.2 Create cart page
7.3 Display message based on action
7.4 Display cart items
7.5 Read products by IDs
7.6 Output

8.0 How to update cart?
8.1 Update cart quantity with JavaScript
8.2 PHP script to update cart
8.3 How to remove product on cart?
8.4 Create the checkout page
8.5 Create place_order.php
8.6 Output

9.0 How to make the product page?
9.1 Create product.php
9.2 Read product details
9.3 Read one product method
9.4 Display product thumbnails
9.5 Read images related to product
9.6 Display product image
9.7 Make image hover work
9.8 Display product details
9.9 Render 'Cart' button
9.10 Output

10.0 What people say about this code?
11.0 How to run the source code?

12.0 Download LEVEL 1 source code
13.0 Download LEVEL 2 source code

14.0 PHP Shopping Cart Module
15.0 PHP Shopping Cart System

16.0 What’s Next?
17.0 Related Tutorials
18.0 Some Notes

1.0 Overview

1.1 Introduction

If you want to build your own online shopping cart from scratch, we have good news for you!

This post can help you get it done because we will build a simple shopping cart script today.

We will use PHP, MySQL and PHP sessions to complete this task.

A lot of people use a ready-made software for this.

But for coders like us, it is important to learn and experience how to do it. We can create more features like making the system more secured, add some unique functionality and more.

Your imagination can be the only limit.

1.2 Is this code for you?

The source codes in this page is NOT for you if:

  • You are already an expert in PHP & MySQL programming.
  • You have a lot of time to code a shopping cart system from scratch.
  • You are not that interested in learning PHP & MySQL programming.

But, this SOURCE CODE is FOR YOU if:

  • You want to SAVE huge amount of development time.
  • You want to develop your own shopping cart system from scratch.
  • You determined to learn how to make a web application in PHP & MySQL.

But if you are an expert in PHP & MySQL programming and would like to take a look at our code, please do so! We'd love to hear your response and great insights! The comments section below is always open for anyone with questions and suggestions.

1.3 How to use this tutorial?

This tutorial is already working. You can proceed to the instructions below.

But we are recording a video demo about how to use this tutorial.

It is coming soon! Please subscribe here so you will be updated.

2.0 Tutorial Output Preview

Below are some screenshots of our script’s output. You can click an image to view the larger version of it. Use the left and right arrow to navigate through the screenshots.

Please note that the following images are just output previews. New features might be added already the time you are reading this.

2.1 LEVEL 1 Source Code Output


2.2 LEVEL 2 Source Code Output


The LEVEL 2 source code output proves that you can add and customize more features. It will be easier and faster if you will learn by following our tutorial below.

Downloading our source codes is your huge advantage as well.

If you need more features like product variations, admin features and user login, see our PHP Shopping Cart Module and PHP Shopping Cart System.

For now, let's proceed to the step by step tutorial of our LEVEL 1 source code. Enjoy!

3.0 File Structure

The following folders and files are included in the final source code of this tutorial. It will have more meaning if you will see the code inside the folders and files as we go through this tutorial.

The branch with backslash represents a folder. Everything else represents a file. It can be a PHP file, SQL file, text file, CSS file or JavaScript file.

├─ config/
├─── database.php
├─ dev/
├─── shop_cart_sessions_1.sql
├─── readme.txt
├─ images/
├─ libs/
├─── css/
├────── bootstrap/
├─── js/
├────── jquery.js
├─ objects/
├─── product_image.php
├─── product.php
├─ uploads/
├─── images/
├─ .htaccess
├─ add_to_cart.php
├─ cart.php
├─ checkout.php
├─ layout_footer.php
├─ layout_header.php
├─ navigation.php
├─ paging.php
├─ place_order.php
├─ product.php
├─ products.php
├─ read_products_template.php
├─ remove_from_cart.php
├─ update_quantity.php

4.0 Prepare the database

4.1 Database Design

Our database name will be called "shop_cart_sessions_1", and we will have two (2) tables. The image below is a visual representation of our database tables and how they are related.
php shopping cart tutorial database design

4.2 Create a database

Make sure your Apache and MySQL servers are running.

  • Open your PhpMyAdmin (http://localhost/phpmyadmin)
  • Create a new database.
  • Put "shop_cart_sessions_1" as database name.
  • Click "Create" button.

4.3 Create "products" table

In this section, we will create the "products" table (using PhpMyAdmin) on the database we just created. This table will hold the product records.

Here's how to run an SQL statement using PhpMyAdmin.

  • Click "shop_cart_sessions_1" database.
  • Click "SQL" tab.
  • Copy the SQL statement below and paste it in the text area.
  • Click the "Go" button.
CREATE TABLE IF NOT EXISTS `products` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(512) NOT NULL,
  `description` text NOT NULL,
  `price` decimal(10,2) NOT NULL,
  `created` datetime NOT NULL,
  `modified` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM  DEFAULT CHARSET=latin1 COMMENT='products that can be added to cart' AUTO_INCREMENT=41 ;

4.4 Create "categories" table

This table will hold images related to product.

Run the following SQL statement using your PhpMyAdmin.

CREATE TABLE IF NOT EXISTS `product_images` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `product_id` int(11) NOT NULL,
  `name` varchar(512) NOT NULL,
  `created` datetime NOT NULL,
  `modified` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 COMMENT='image files related to a product' AUTO_INCREMENT=105 ;

4.5 Download sample data and images

The products and product_images table will not fully work without the sample data and related image files.

To make things easier, I decided to create a ZIP file with shop_cart_sessions_1.sql and 28 image files inside (1.30 MB).

Use the following button to download the ZIP file.

4.6 Extract and import data

Once downloaded, please extract the files.

Import the SQL file using PhpMyAdmin.

Put the image files in "php-shopping-cart-using-sessions-level-1/uploads/images/" directory. That directory does not exist yet. We need to create it now.

  • Create "php-shopping-cart-using-sessions-level-1" folder and open it. This is our project's main folder.
  • Create "uploads" folder and open it.
  • Create "images" folder and open it.
  • Copy and paste the images on this directory.

4.7 Database connection file

This file will be used to get connection to the database.

  • Open "php-shopping-cart-using-sessions-level-1" folder.
  • Create "config" folder and open it.
  • Create "database.php" file and open it.
  • Place the following code.
<?php
// used to get mysql database connection
class Database{

	// specify your own database credentials
	private $host = "localhost";
	private $db_name = "shop_cart_sessions_1";
	private $username = "root";
	private $password = "";
	public $conn;

	// get the database connection
	public function getConnection(){

		$this->conn = null;

		try{
			$this->conn = new PDO("mysql:host=" . $this->host . ";dbname=" . $this->db_name, $this->username, $this->password);
		}catch(PDOException $exception){
			echo "Connection error: " . $exception->getMessage();
		}

		return $this->conn;
	}

}
?>

4.8 Output

Our PhpMyAdmin should look like the image below. A database with two tables.

We don't have an actual program output yet because we only set up the database. Let's continue our tutorial below to achieve more outputs.

5.0 Create the layout files

5.1 Create header layout file

This “layout_header.php” file will be included at the beginning of the PHP files that will need it. This way, we won’t have to write the same header codes every time.

We use the Bootstrap framework to make our project look good. If you’re not yet familiar with you, please learn our Bootstrap tutorial here.

Bootstrap CSS asset will be included inside the head tags.

  • Open "php-shopping-cart-using-sessions-level-1" folder.
  • Create "layout_header.php" file.
  • Place the following code.
<?php
$_SESSION['cart']=isset($_SESSION['cart']) ? $_SESSION['cart'] : array();
?>
<!DOCTYPE html>
<html lang="en">
<head>

    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">

    <title><?php echo isset($page_title) ? $page_title : "The Code of a Ninja"; ?></title>

    <!-- Latest compiled and minified Bootstrap CSS -->
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" />
  
    <!-- our custom CSS -->
    <link rel="stylesheet" href="libs/css/custom.css" />

</head>
<body>

	<?php include 'navigation.php'; ?>

    <!-- container -->
    <div class="container">
        <div class="row">

        <div class="col-md-12">
            <div class="page-header">
                <h1><?php echo isset($page_title) ? $page_title : "The Code of a Ninja"; ?></h1>
            </div>
        </div>

5.2 Create footer layout file

This "layout_footer.php" will be included at the end of the PHP files that will needs it. This way, we won’t have to write the same footer codes every time.

The assets used in this file are:

Let’s go on and create the footer layout file.

  • Open "php-shopping-cart-using-sessions-level-1" folder.
  • Create "layout_footer.php" file.
  • Place the following code.
		</div>
		<!-- /row -->

	</div>
	<!-- /container -->

<!-- jQuery (necessary for Bootstrap's JavaScript plugins) -->
<script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>
 
<!-- Latest compiled and minified Bootstrap JavaScript -->
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>

<!-- custom script will be here -->

</body>
</html>

5.3 Create navigation layout file

This file will render the "Products" and "Cart" links that the user can click.

  • Open "php-shopping-cart-using-sessions-level-1" folder.
  • Create "navigation.php" file.
  • Place the following code.
<!-- navbar -->
<div class="navbar navbar-default navbar-static-top" role="navigation">
	<div class="container">

		<div class="navbar-header">
			<button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
			<span class="sr-only">Toggle navigation</span>
			<span class="icon-bar"></span>
			<span class="icon-bar"></span>
			<span class="icon-bar"></span>
			</button>
			<a class="navbar-brand" href="products.php">XYZ Webstore</a>
		</div>

		<div class="navbar-collapse collapse">
			<ul class="nav navbar-nav">

				<!-- highlight if $page_title has 'Products' word. -->
				<li <?php echo $page_title=="Products" ? "class='active'" : ""; ?>>
					<a href="products.php" class="dropdown-toggle">Products</a>
				</li>

				<li <?php echo $page_title=="Cart" ? "class='active'" : ""; ?> >
					<a href="cart.php">
						<?php
						// count products in cart
						$cart_count=count($_SESSION['cart']);
						?>
						Cart <span class="badge" id="comparison-count"><?php echo $cart_count; ?></span>
					</a>
				</li>
			</ul>

		</div><!--/.nav-collapse -->

	</div>
</div>
<!-- /navbar -->

5.4 Create custom CSS file

This custom.css file is where our custom styles are located.

  • Open "php-shopping-cart-using-sessions-level-1" folder.
  • Open "libs" folder.
  • Open "css" folder.
  • Create "custom.css" file.
  • Place the following code.
.text-align-center{ text-align:center; }
.f-w-b{ font-weight:bold; }
.display-none{ display:none; }

.w-5-pct{ width:5%; }
.w-10-pct{ width:10%; }
.w-15-pct{ width:15%; }
.w-20-pct{ width:20%; }
.w-25-pct{ width:25%; }
.w-30-pct{ width:30%; }
.w-35-pct{ width:35%; }
.w-40-pct{ width:40%; }
.w-45-pct{ width:45%; }
.w-50-pct{ width:50%; }
.w-55-pct{ width:55%; }
.w-60-pct{ width:60%; }
.w-65-pct{ width:65%; }
.w-70-pct{ width:70%; }
.w-75-pct{ width:75%; }
.w-80-pct{ width:80%; }
.w-85-pct{ width:85%; }
.w-90-pct{ width:90%; }
.w-95-pct{ width:95%; }
.w-100-pct{ width:100%; }

.m-t-0px{ margin-top:0px; }
.m-b-10px{ margin-bottom:10px; }
.m-b-20px{ margin-bottom:20px; }
.m-b-30px{ margin-bottom:30px; }
.m-b-40px{ margin-bottom:40px; }

.stock-text {
    font-weight: bold;
    color: #008a00;
}

.stock-text-red{
    font-weight:bold;
    color:#b12704;
}

.product-detail {
    font-weight: bold;
    margin: 0 0 5px 0;
}

.blueimp-gallery>.prev, .blueimp-gallery>.next{ border:none; }

.update-quantity-form {
    width: 150px;
    float: left;
    margin: 0 10px 0 0;
}

.cart-row {
    border-bottom: thin solid #f1f1f1;
    overflow: hidden;
    width: 100%;
    padding: 20px 0 20px 0;
}

.product-link{
    color:#000000;
}

.product-link:hover{
    color:#000000;
    text-decoration:none;
}

.product-img-thumb {
    margin: 0 0 10px 0;
    width: 100%;
    cursor: pointer;
}

5.5 Output

The files we created in this section is meant to be used within another PHP file. If we will try to run the files, we won't see anything meaningful yet.

If you will run layout_header.php file, it will look like this.

The custom.css looks like this.

The navigation.php looks like this.

The footer.php is blank. Let's continue on the next section to see something meaningful.

6.0 Display Products

6.1 Create products.php

Now we are going to start displaying products from the database. Create products.php with the following basic code.

<?php
// start session
session_start();

// set page title
$page_title="Products";

// page header html
include 'layout_header.php';

// contents will be here 

// layout footer code
include 'layout_footer.php';
?>

6.2 Include PHP Classes

Put the following code after "session_start();" code of the previous section.

// connect to database
include 'config/database.php';

// include objects
include_once "objects/product.php";
include_once "objects/product_image.php";

// class instances will be here

6.3 Create "product" object file

Create "objects" folder. Inside it, create product.php file with the following code.

<?php
// 'product' object
class Product{

	// database connection and table name
	private $conn;
	private $table_name="products";

	// object properties
	public $id;
	public $name;
	public $price;
	public $description;
	public $category_id;
	public $category_name;
	public $timestamp;

	// constructor
	public function __construct($db){
		$this->conn = $db;
	}
}

6.4 Create "product image" object file

Create product_image.php file inside "objects" folder.

<?php
// 'product image' object
class ProductImage{

	// database connection and table name
	private $conn;
	private $table_name = "product_images";

	// object properties
	public $id;
	public $product_id;
	public $name;
	public $timestamp;

	// constructor
	public function __construct($db){
		$this->conn = $db;
	}
}

6.5 Connect to the database

Open products.php file. Replace // class instances will be here comment with the following code.

// get database connection
$database = new Database();
$db = $database->getConnection();

// initialize objects
$product = new Product($db);
$product_image = new ProductImage($db);

6.6 Initialize action and pagination

Put the following code after the code on the previous section.

// to prevent undefined index notice
$action = isset($_GET['action']) ? $_GET['action'] : "";

// for pagination purposes
$page = isset($_GET['page']) ? $_GET['page'] : 1; // page is the current page, if there's nothing set, default is page 1
$records_per_page = 6; // set records or rows of data per page
$from_record_num = ($records_per_page * $page) - $records_per_page; // calculate for the query LIMIT clause

6.7 Display messages based on action

We'll display messages basedon given action.

Put the following code after include 'layout_header.php'; code.

echo "<div class='col-md-12'>";
	if($action=='added'){
		echo "<div class='alert alert-info'>";
			echo "Product was added to your cart!";
		echo "</div>";
	}

	if($action=='exists'){
		echo "<div class='alert alert-info'>";
			echo "Product already exists in your cart!";
		echo "</div>";
	}
echo "</div>";

6.8 Request data from the database

Request data from the database. Put the following code after the code on the previous section.

// read all products in the database
$stmt=$product->read($from_record_num, $records_per_page);

// count number of retrieved products
$num = $stmt->rowCount();

// if products retrieved were more than zero
if($num>0){
	// needed for paging
	$page_url="products.php?";
	$total_rows=$product->count();

	// show products
	include_once "read_products_template.php";
}

// tell the user if there's no products in the database
else{
	echo "<div class='col-md-12'>";
    	echo "<div class='alert alert-danger'>No products found.</div>";
	echo "</div>";
}

6.9 Add "read" and "count" methods

The previous section will not work without the following code inside "objects/product.php" object file.

// read all products
function read($from_record_num, $records_per_page){

	// select all products query
	$query = "SELECT
				id, name, description, price 
			FROM
				" . $this->table_name . "
			ORDER BY
				created DESC
			LIMIT
				?, ?";

	// prepare query statement
	$stmt = $this->conn->prepare( $query );

	// bind limit clause variables
	$stmt->bindParam(1, $from_record_num, PDO::PARAM_INT);
	$stmt->bindParam(2, $records_per_page, PDO::PARAM_INT);

	// execute query
	$stmt->execute();

	// return values
	return $stmt;
}

// used for paging products
public function count(){

	// query to count all product records
	$query = "SELECT count(*) FROM " . $this->table_name;

	// prepare query statement
	$stmt = $this->conn->prepare( $query );

	// execute query
	$stmt->execute();

	// get row value
	$rows = $stmt->fetch(PDO::FETCH_NUM);

	// return count
	return $rows[0];
}

6.10 Template to display products

The products.php won't work without "read_products_template.php", so create that file and put the following code.

<?php
if(!isset($_SESSION['cart'])){
	$_SESSION['cart']=array();
}

while ($row = $stmt->fetch(PDO::FETCH_ASSOC)){
	extract($row);

	// creating box
	echo "<div class='col-md-4 m-b-20px'>";

		// product id for javascript access
		echo "<div class='product-id display-none'>{$id}</div>";

		echo "<a href='product.php?id={$id}' class='product-link'>";
			// select and show first product image
			$product_image->product_id=$id;
			$stmt_product_image=$product_image->readFirst();

			while ($row_product_image = $stmt_product_image->fetch(PDO::FETCH_ASSOC)){
				echo "<div class='m-b-10px'>";
					echo "<img src='uploads/images/{$row_product_image['name']}' class='w-100-pct' />";
				echo "</div>";
			}

			// product name
			echo "<div class='product-name m-b-10px'>{$name}</div>";
		echo "</a>";

		// add to cart button
		echo "<div class='m-b-10px'>";
			if(array_key_exists($id, $_SESSION['cart'])){
				echo "<a href='cart.php' class='btn btn-success w-100-pct'>";
					echo "Update Cart";
				echo "</a>";
			}else{
				echo "<a href='add_to_cart.php?id={$id}&page={$page}' class='btn btn-primary w-100-pct'>Add to Cart</a>";
			}
		echo "</div>";

	echo "</div>";
}

include_once "paging.php";
?>

6.11 Add "readFirst()" method

Add "readFirst()" method in "objects/product_image.php" file. The previous section will not work without it.

// read the first product image related to a product
function readFirst(){

	// select query
	$query = "SELECT id, product_id, name
			FROM " . $this->table_name . "
			WHERE product_id = ?
			ORDER BY name DESC
			LIMIT 0, 1";

	// prepare query statement
	$stmt = $this->conn->prepare( $query );

	// sanitize
	$this->id=htmlspecialchars(strip_tags($this->id));

	// bind prodcut id variable
	$stmt->bindParam(1, $this->product_id);

	// execute query
	$stmt->execute();

	// return values
	return $stmt;
}

6.12 Make "add to cart" button work

Open layout_footer.php file. Replace <!-- custom script will be here --> comment with the following code.

<script>
$(document).ready(function(){
	// add to cart button listener
	$('.add-to-cart-form').on('submit', function(){

		// info is in the table / single product layout
		var id = $(this).find('.product-id').text();
		var quantity = $(this).find('.cart-quantity').val();

		// redirect to add_to_cart.php, with parameter values to process the request
		window.location.href = "add_to_cart.php?id=" + id + "&quantity=" + quantity;
		return false;
	});
});
</script>

6.13 Create pagination file

The read_products_template.php file won't work without the paging.php file. Create paging.php with the following code.

<?php
echo "<div class='col-md-12'>";

    echo "<ul class='pagination m-b-20px m-t-0px'>";

    // button for first page
    if($page>1){
        echo "<li><a href='{$page_url}' title='Go to the first page.'>";
            echo "First Page";
        echo "</a></li>";
    }

    $total_pages = ceil($total_rows / $records_per_page);

    // range of links to show
    $range = 2;

    // display links to 'range of pages' around 'current page'
    $initial_num = $page - $range;
    $condition_limit_num = ($page + $range)  + 1;

    for ($x=$initial_num; $x<$condition_limit_num; $x++) {

        // be sure '$x is greater than 0' AND 'less than or equal to the $total_pages'
        if (($x > 0) && ($x <= $total_pages)) {

            // current page
            if ($x == $page) {
                echo "<li class='active'><a href=\"#\">$x <span class=\"sr-only\">(current)</span></a></li>";
            }

            // not current page
            else {
                echo "<li><a href='{$page_url}page=$x'>$x</a></li>";
            }
        }
    }

    // button for last page
    if($page<$total_pages){
        echo "<li>";
            echo "<a href='" . $page_url . "page={$total_pages}' title='Last page is {$total_pages}.'>";
                echo "Last Page";
            echo "</a>";
        echo "</li>";
    }

    echo "</ul>";
echo "</div>";
?>

6.14 Output

Run your products.php file on the browser http://localhost/php-shopping-cart-using-sessions-level-1/products.php. You should see an output like the image below.

7.0 How to add to cart?

7.1 Create add_to_cart.php

Create add_to_cart.php file because when 'Add to cart' button was clicked, that file with the following code inside will be executed.

<?php
// start session 
session_start();

// get the product id
$id = isset($_GET['id']) ? $_GET['id'] : "";
$quantity = isset($_GET['quantity']) ? $_GET['quantity'] : 1;
$page = isset($_GET['page']) ? $_GET['page'] : 1;

// make quantity a minimum of 1
$quantity=$quantity<=0 ? 1 : $quantity;

// add new item on array
$cart_item=array(
	'quantity'=>$quantity
);

/*
 * check if the 'cart' session array was created
 * if it is NOT, create the 'cart' session array
 */
if(!isset($_SESSION['cart'])){
	$_SESSION['cart'] = array();
}

// check if the item is in the array, if it is, do not add
if(array_key_exists($id, $_SESSION['cart'])){
	// redirect to product list and tell the user it was added to cart
	header('Location: products.php?action=exists&id=' . $id . '&page=' . $page);
}

// else, add the item to the array
else{
	$_SESSION['cart'][$id]=$cart_item;

	// redirect to product list and tell the user it was added to cart
	header('Location: products.php?action=added&page=' . $page);
}
?>

7.2 Create cart.php

Create cart.php with the following basic code.

<?php
// start session
session_start();

// connect to database
include 'config/database.php';

// include objects
include_once "objects/product.php";
include_once "objects/product_image.php";

// get database connection
$database = new Database();
$db = $database->getConnection();

// initialize objects
$product = new Product($db);
$product_image = new ProductImage($db);

// set page title
$page_title="Cart";

// include page header html
include 'layout_header.php';

// contents will be here 

// layout footer 
include 'layout_footer.php';
?>

7.3 Display message based on action

We'll display message on cart.php based on given action.

Put the following code after include 'layout_header.php'; of the previous section.

$action = isset($_GET['action']) ? $_GET['action'] : "";

echo "<div class='col-md-12'>";
	if($action=='removed'){
		echo "<div class='alert alert-info'>";
			echo "Product was removed from your cart!";
		echo "</div>";
	}

	else if($action=='quantity_updated'){
		echo "<div class='alert alert-info'>";
			echo "Product quantity was updated!";
		echo "</div>";
	}
echo "</div>";

7.4 Display cart items

Put the following code after the code of the previous section.

if(count($_SESSION['cart'])>0){

	// get the product ids
	$ids = array();
	foreach($_SESSION['cart'] as $id=>$value){
		array_push($ids, $id);
	}

	$stmt=$product->readByIds($ids);

	$total=0;
	$item_count=0;

	while ($row = $stmt->fetch(PDO::FETCH_ASSOC)){
        extract($row);

		$quantity=$_SESSION['cart'][$id]['quantity'];
		$sub_total=$price*$quantity;

		// =================
		echo "<div class='cart-row'>";
			echo "<div class='col-md-8'>";

				echo "<div class='product-name m-b-10px'><h4>{$name}</h4></div>";

				// update quantity
				echo "<form class='update-quantity-form'>";
					echo "<div class='product-id' style='display:none;'>{$id}</div>";
					echo "<div class='input-group'>";
						echo "<input type='number' name='quantity' value='{$quantity}' class='form-control cart-quantity' min='1' />";
							echo "<span class='input-group-btn'>";
								echo "<button class='btn btn-default update-quantity' type='submit'>Update</button>";
							echo "</span>";
					echo "</div>";
				echo "</form>";

				// delete from cart
				echo "<a href='remove_from_cart.php?id={$id}' class='btn btn-default'>";
					echo "Delete";
				echo "</a>";
			echo "</div>";

			echo "<div class='col-md-4'>";
				echo "<h4>&#36;" . number_format($price, 2, '.', ',') . "</h4>";
			echo "</div>";
		echo "</div>";
		// =================

		$item_count += $quantity;
		$total+=$sub_total;
	}

	echo "<div class='col-md-8'></div>";
	echo "<div class='col-md-4'>";
		echo "<div class='cart-row'>";
			echo "<h4 class='m-b-10px'>Total ({$item_count} items)</h4>";
			echo "<h4>&#36;" . number_format($total, 2, '.', ',') . "</h4>";
	        echo "<a href='checkout.php' class='btn btn-success m-b-10px'>";
	        	echo "<span class='glyphicon glyphicon-shopping-cart'></span> Proceed to Checkout";
	        echo "</a>";
		echo "</div>";
	echo "</div>";

}

// no products were added to cart
else{
	echo "<div class='col-md-12'>";
		echo "<div class='alert alert-danger'>";
			echo "No products found in your cart!";
		echo "</div>";
	echo "</div>";
}

7.5 Read products by IDs

The previous section will not work without the following "readByIds()" method inside "objects/product.php" file.

// read all product based on product ids included in the $ids variable
// reference http://stackoverflow.com/a/10722827/827418
public function readByIds($ids){

	$ids_arr = str_repeat('?,', count($ids) - 1) . '?';

	// query to select products
	$query = "SELECT id, name, price FROM " . $this->table_name . " WHERE id IN ({$ids_arr}) ORDER BY name";

	// prepare query statement
	$stmt = $this->conn->prepare($query);

	// execute query
	$stmt->execute($ids);

	// return values from database
	return $stmt;
}

7.6 Output

When user click the "Add to cart" button.

Go to the cart page by clicking the "Cart" option on the navigation bar.

8.0 How to update cart?

8.1 Update cart quantity with JavaScript

We have the 'update' button on cart.php file. When that button was clicked, a javascript code is triggered.

Place the following code inside $(document).ready(function(){ of layout_footer.php file.

// update quantity button listener
$('.update-quantity-form').on('submit', function(){

	// get basic information for updating the cart
	var id = $(this).find('.product-id').text();
	var quantity = $(this).find('.cart-quantity').val();

	// redirect to update_quantity.php, with parameter values to process the request
	window.location.href = "update_quantity.php?id=" + id + "&quantity=" + quantity;
	return false;
});

8.2 PHP script to update cart

The previous section will not work without this file.

Create update_quantity.php file. Place the following code and save it.

<?php
session_start();

// get the product id
$id = isset($_GET['id']) ? $_GET['id'] : 1;
$quantity = isset($_GET['quantity']) ? $_GET['quantity'] : "";

// make quantity a minimum of 1
$quantity=$quantity<=0 ? 1 : $quantity;

// remove the item from the array
unset($_SESSION['cart'][$id]);

// add the item with updated quantity
$_SESSION['cart'][$id]=array(
	'quantity'=>$quantity
);

// redirect to product list and tell the user it was added to cart
header('Location: cart.php?action=quantity_updated&id=' . $id);
?>

8.3 How to remove product on cart?

We have the 'remove' button on cart.php file. When that button was clicked, it will trigger remove_from_cart.php file.

Create remove_from_cart.php file. Place the following code and save it.

<?php
// start session
session_start();

// get the product id
$id = isset($_GET['id']) ? $_GET['id'] : "";
$name = isset($_GET['name']) ? $_GET['name'] : "";

// remove the item from the array
unset($_SESSION['cart'][$id]);

// redirect to product list and tell the user it was added to cart
header('Location: cart.php?action=removed&id=' . $id);
?>

8.4 Create the checkout page

The checkout page looks like the cart page but the items cannot be updated or removed. It just like the summary of orders. Create checkout.php with the following code.

<?php
// start session
session_start();

// connect to database
include 'config/database.php';

// include objects
include_once "objects/product.php";
include_once "objects/product_image.php";

// get database connection
$database = new Database();
$db = $database->getConnection();

// initialize objects
$product = new Product($db);
$product_image = new ProductImage($db);

// set page title
$page_title="Checkout";

// include page header html
include 'layout_header.php';

if(count($_SESSION['cart'])>0){

	// get the product ids
	$ids = array();
	foreach($_SESSION['cart'] as $id=>$value){
		array_push($ids, $id);
	}

	$stmt=$product->readByIds($ids);

	$total=0;
	$item_count=0;

	while ($row = $stmt->fetch(PDO::FETCH_ASSOC)){
        extract($row);

		$quantity=$_SESSION['cart'][$id]['quantity'];
		$sub_total=$price*$quantity;

		//echo "<div class='product-id' style='display:none;'>{$id}</div>";
		//echo "<div class='product-name'>{$name}</div>";

		// =================
		echo "<div class='cart-row'>";
			echo "<div class='col-md-8'>";

				echo "<div class='product-name m-b-10px'><h4>{$name}</h4></div>";
                echo $quantity>1 ? "<div>{$quantity} items</div>" : "<div>{$quantity} item</div>";

			echo "</div>";

			echo "<div class='col-md-4'>";
				echo "<h4>&#36;" . number_format($price, 2, '.', ',') . "</h4>";
			echo "</div>";
		echo "</div>";
		// =================

		$item_count += $quantity;
		$total+=$sub_total;
	}

	// echo "<div class='col-md-8'></div>";
	echo "<div class='col-md-12 text-align-center'>";
		echo "<div class='cart-row'>";
            if($item_count>1){
    			echo "<h4 class='m-b-10px'>Total ({$item_count} items)</h4>";
            }else{
                echo "<h4 class='m-b-10px'>Total ({$item_count} item)</h4>";
            }
			echo "<h4>&#36;" . number_format($total, 2, '.', ',') . "</h4>";
	        echo "<a href='place_order.php' class='btn btn-lg btn-success m-b-10px'>";
	        	echo "<span class='glyphicon glyphicon-shopping-cart'></span> Place Order";
	        echo "</a>";
		echo "</div>";
	echo "</div>";

}

else{
	echo "<div class='col-md-12'>";
		echo "<div class='alert alert-danger'>";
			echo "No products found in your cart!";
		echo "</div>";
	echo "</div>";
}

include 'layout_footer.php';
?>

8.5 Create place_order.php

We'll use this file to show a "thank you" message and remove all items in the cart.

Create place_order.php file. Place the following code.

<?php
// start session
session_start();

// remove items from the cart
session_destroy();

// set page title
$page_title="Thank You!";

// include page header HTML
include_once 'layout_header.php';

echo "<div class='col-md-12'>";

	// tell the user order has been placed
	echo "<div class='alert alert-success'>";
		echo "<strong>Your order has been placed!</strong> Thank you very much!";
	echo "</div>";

echo "</div>";

// include page footer HTML
include_once 'layout_footer.php';
?>

8.6 Output

When user click the "Update" button in the cart page.

If user click the "Delete" button.

The checkout page.

When user click the "Place Order" button.

9.0 How to make the product page?

9.1 Create product.php

Create product.php with the following basic code.

<?php
// start session
session_start();

// include classes
include_once "config/database.php";
include_once "objects/product.php";
include_once "objects/product_image.php";

// get database connection
$database = new Database();
$db = $database->getConnection();

// initialize objects
$product = new Product($db);
$product_image = new ProductImage($db);

// include page header HTML
include_once 'layout_header.php';

// content will be here

// include page footer HTML
include_once 'layout_footer.php';
?>

9.2 Read product details

Put the following code after "$product_image = new ProductImage($db);" code of the previous section.

// get ID of the product to be edited
$id = isset($_GET['id']) ? $_GET['id'] : die('ERROR: missing ID.');

// set the id as product id property
$product->id = $id;

// to read single record product
$product->readOne();

// set page title
$page_title = $product->name;

// product thumbnail will be here

9.3 Read one product method

The previous section will not work without the "readOne()" method. Add the following method inside "objects/product.php" file.

// used when filling up the update product form
function readOne(){

	// query to select single record
	$query = "SELECT
				name, description, price
			FROM
				" . $this->table_name . "
			WHERE
				id = ?
			LIMIT
				0,1";

	// prepare query statement
	$stmt = $this->conn->prepare( $query );

	// sanitize
	$this->id=htmlspecialchars(strip_tags($this->id));

	// bind product id value
	$stmt->bindParam(1, $this->id);

	// execute query
	$stmt->execute();

	// get row values
	$row = $stmt->fetch(PDO::FETCH_ASSOC);

	// assign retrieved row value to object properties
	$this->name = $row['name'];
	$this->description = $row['description'];
	$this->price = $row['price'];
}

9.4 Display product thumbnails

When these product thumbnails were hovered, it displayes a larger version of the image. It is Amazon-style.

Open product.php file. Replace // product thumbnail will be here comment with the following code.

// set product id
$product_image->product_id=$id;

// read all related product image
$stmt_product_image = $product_image->readByProductId();

// count all relatd product image
$num_product_image = $stmt_product_image->rowCount();

echo "<div class='col-md-1'>";
	// if count is more than zero
	if($num_product_image>0){
		// loop through all product images
		while ($row = $stmt_product_image->fetch(PDO::FETCH_ASSOC)){
			// image name and source url
			$product_image_name = $row['name'];
			$source="uploads/images/{$product_image_name}";
			echo "<img src='{$source}' class='product-img-thumb' data-img-id='{$row['id']}' />";
		}
	}else{ echo "No images."; }
echo "</div>";

// product image will be here

9.5 Read images related to product

The previous section section will not work without the "readByProductId()" method inside "objects/product_image.php" file.

// read all product image related to a product
function readByProductId(){

	// select query
	$query = "SELECT id, product_id, name
			FROM " . $this->table_name . "
			WHERE product_id = ?
			ORDER BY name ASC";

	// prepare query statement
	$stmt = $this->conn->prepare( $query );

	// sanitize
	$this->product_id=htmlspecialchars(strip_tags($this->product_id));

	// bind prodcut id variable
	$stmt->bindParam(1, $this->product_id);

	// execute query
	$stmt->execute();

	// return values
	return $stmt;
}

9.6 Display product image

Only one product image are displayed at a time. This part displays the larger product image based on the hovered product thumbnail.

Open product.php file. Replace // product image will be here comment with the following code.

echo "<div class='col-md-4' id='product-img'>";

	// read all related product image
	$stmt_product_image = $product_image->readByProductId();
	$num_product_image = $stmt_product_image->rowCount();

	// if count is more than zero
	if($num_product_image>0){
		// loop through all product images
		$x=0;
		while ($row = $stmt_product_image->fetch(PDO::FETCH_ASSOC)){
			// image name and source url
			$product_image_name = $row['name'];
			$source="uploads/images/{$product_image_name}";
			$show_product_img=$x==0 ? "display-block" : "display-none";
			echo "<a href='{$source}' target='_blank' id='product-img-{$row['id']}' class='product-img {$show_product_img}'>";
				echo "<img src='{$source}' style='width:100%;' />";
			echo "</a>";
			$x++;
		}
	}else{ echo "No images."; }
echo "</div>";

// product details will be here

9.7 Make image hover work

Put the following jQuery code inside "$(document).ready(function(){" of layout_footer.php file.

// change product image on hover
$(document).on('mouseenter', '.product-img-thumb', function(){
	var data_img_id = $(this).attr('data-img-id');
	$('.product-img').hide();
	$('#product-img-'+data_img_id).show();
});

9.8 Display product details

This part display product price, description and category.

Open product.php file. Replace // product details will be here comment with the following code.

echo "<div class='col-md-5'>";

	echo "<div class='product-detail'>Price:</div>";
	echo "<h4 class='m-b-10px price-description'>&#36;" . number_format($product->price, 2, '.', ',') . "</h4>";

	echo "<div class='product-detail'>Product description:</div>";
	echo "<div class='m-b-10px'>";
		// make html
		$page_description = htmlspecialchars_decode(htmlspecialchars_decode($product->description));

		// show to user
		echo $page_description;
	echo "</div>";

	echo "<div class='product-detail'>Product category:</div>";
	echo "<div class='m-b-10px'>{$product->category_name}</div>";

echo "</div>";

9.9 Render 'Cart' button

Now we will display 'Add to cart' button if the product is not yet added to cart. Else, we will display 'update cart' button.

Place the following code after the previous section's code.

echo "<div class='col-md-2'>";

	// if product was already added in the cart
	if(array_key_exists($id, $_SESSION['cart'])){
		echo "<div class='m-b-10px'>This product is already in your cart.</div>";
		echo "<a href='cart.php' class='btn btn-success w-100-pct'>";
			echo "Update Cart";
		echo "</a>";

	}

	// if product was not added to the cart yet
	else{

		echo "<form class='add-to-cart-form'>";
			// product id
			echo "<div class='product-id display-none'>{$id}</div>";

			echo "<div class='m-b-10px f-w-b'>Quantity:</div>";
			echo "<input type='number' value='1' class='form-control m-b-10px cart-quantity' min='1' />";

			// enable add to cart button
			echo "<button style='width:100%;' type='submit' class='btn btn-primary add-to-cart m-b-10px'>";
				echo "<span class='glyphicon glyphicon-shopping-cart'></span> Add to cart";
			echo "</button>";

		echo "</form>";
	}
echo "</div>";

9.10 Output

When user click on any product image in products.php page, he will land to a product page that looks like the image below.


If user hovers on any of those thumbnail or small images, the big image will change as well. The "Add to cart" button is working as well.

Here's the output when the product is already added to cart.

If user click the "Update Cart" button, he will land on the cart page where he can update the cart quantity.

10.0 What People Say About This Code?

I'm so glad that this code delights other people. The following are some of them from the comments section!

★★★★★ "Hey Mike, my name is Leonardo from Argentina. I've been reading your blog since like 4 months from now, and I really must say: your tutorials are very good, they has helped me in many of my works... Well, thank you very much man. I really admire your work." ~ Leonardo

★★★★★ "Man, your tut's are awesome. Im so glad ive found your blog. Big respect!" ~ Milos

★★★★★ "I bought your level-2 source code and it was so good, very big help for me. It was worth it. Thank you very much!" ~ Ashley Deanna Plata

★★★★★ "Hello, This is a great script and I have paid for your work (it Worth it)." ~ Louis Blais

★★★★★ "Words can't express how grateful I am for the work and the articles you post, had some troubles with doing somethings but your articles as per usual hit the hammer right on the head. They are a great way for expanding upon later too!" ~ Jeremy Smith

11.0 How to run the source code?

We highly recommend for you to follow and study our well-detailed, step-by-step tutorial above first. Nothing beats experience when it comes to learning.

But we believe you will learn faster if you’ll see the final source code as well. We consider it as your additional guide.

Imagine the value or skill upgrade it can bring you. The additional income you can get from your work, projects or business. The precious time you save. Isn’t that what you want?

By now, you need to download our source codes. To do it, use any download buttons in the next few sections below.

Once you downloaded the source codes, here’s how you can run it.

  1. Extract the files to your server directory.
  2. Go to your PhpMyAdmin, create a database with a name "shop_cart_sessions_1".
  3. Import the "shop_cart_sessions_1.sql" file located in the "README" folder.
  4. You might need to change database credentials in /config/database.php
  5. Run "products.php", this is the main PHP file. We do not have index.php

12.0 Download the LEVEL 1 Source Code

FEATURE LEVEL 1
Learn to code a simple cart function YES
List all products from MySQL database YES
Pagination on products list page YES
Add to cart action button YES
Remove from cart action button Yes
Update cart quantity YES
Checkout Page YES
Place order / Thank you page YES
Amazon-style product details page YES
Change image on hover of thumbnail YES
Show message about a product added to cart YES
Show message about a product removed from cart YES
Navigation bar highlights which page is selected YES
Cart link shows count of products added in the cart YES
Show message if no products found in database YES
Show message if no product found in cart YES
Bootstrap enabled UI YES
Cart page that lists all products added to cart YES
Auto-compute total cost of all products added to cart YES
PDO extension used YES
Step by step tutorial YES
Free source code updates YES
Free support for 6 months YES

THANK YOU!

has been added to your cart!

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Thank you!

have been added to your cart!

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13.0 Download the LEVEL 2 Source Code

FEATURE LEVEL 2
All features of LEVEL 1 source code YES
Navigation bar has drop down of product categories YES
Highlight selected category in drop down YES
Categories are retrieved from the database YES
Show products by category YES
List products under a category with pagination YES
Search product YES
Search results with pagination YES
Search box located on upper right corner of navigation bar YES
Search box requires search term before clicking the search button YES
Add to cart action button YES
Quantity text box beside the add to cart button YES
Quantity text box required to be a number YES
Quantity text box required to have a minimum value of 1, negative value not allowed YES
Remember the page number where the user clicked the "Add to cart" button YES
Quantity drop down options based on available stock YES
Well formatted money value YES
Check out button with cart icon YES
Product image viwable in lightbox YES
Shows number of stock left YES
Stock decreases once checked out YES
Order saved in orders and order_items table in the database YES
Emtpy cart button YES
Emtpy cart confirmation pop up YES
Bootstrap enabled UI YES
Cart page that lists all products added to cart YES
Quantity text box beside update quantity button YES
Show price, category and stocks left in product list page YES
Auto-compute total cost of all products added to cart YES
Used PDO bindParam() to prevent SQL injection in MySQL queries YES
Used PHP htmlspecialchars() to prevent XSS attacks YES
SQL file is in the "dev" folder YES
PDO extension used YES
Free code updates YES
Free support for 6 months YES

THANK YOU!

has been added to your cart!

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Thank you!

have been added to your cart!

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14.0 PHP Shopping Cart Module

You can download our "PHP Shopping Cart & Ordering Module" source code. It has several features you need to learn more about how to handle the users, shopping cart, and ordering using the PHP & MySQL technology. CLICK HERE TO LEARN MORE

15.0 PHP Shopping Cart System

You can download our "PHP Shopping Cart System" source code as well. Many of you requested this type of source code and not it is here!

You needed a shopping cart system with user management (merchant and customer), product management, order management, security and more features based on our source codes here in codeofaninja.com. CLICK HERE TO LEARN MORE.

16.0 What's Next?

You have two options:

Option #1:
We just learned how to code an online shopping cart from scratch using PHP SESSIONS. But did you know that we can create the almost the same functions using another PHP mechanism called COOKIES?

If you're excited to learn this new concept, let us go to the next tutorial: PHP Shopping Cart Tutorial Using COOKIES

Option #2:
This next tutorial is the start of our JavaScript programming journey. Why?

Because this will be used on all our JavaScript programming tutorials. This includes AJAX programming, React, AngularJS, Angular and more.

Go to our next tutorial: How To Create a Simple REST API in PHP – Step By Step Guide!

17.0 Related Tutorials

18.0 Some Notes

#1 Found An Issue?

If you found a problem with this code, we can solve it faster via Email or FB message, please send me a message via email mike@codeofaninja.com, or via our official Facebook page!

Please be more detailed about your issue. Best if you can provide an error message and your test or page URL. Thanks!

Please feel free to comment if you have any questions, suggestions, found something wrong or want to contribute to this code.

#2 Become a true Ninja!

We constantly add new tutorials and improve our existing tutorials and source codes. Be one of the first to know an update by subscribing to our FREE newsletter. Get a FREE EBOOK as well. CLICK HERE TO SUBSCRIBE FOR FREE!

#3 Thank You!

Thank you for studying our tutorial about PHP Shopping Cart Tutorial using SESSIONS!

277 replies
  1. Leonardo
    Leonardo says:

    Hey Mike, my name is Leonardo from Argentina. I’ve been reading your blog since like 4 months from now, and I really must say: your tutorials are very good, they has helped me in many of my works.
    So, I wanted to ask you: Do you think sessions is the right way of doing this?
    I think in a production site this wouldn’t be the best thing to do.
    Shouldn’t you save all the cart stuff in the database right when the user interacts with it? Using some ajax maybe?
    Or is it the idea to save the sessions in the db when the user clicks ‘see cart’ or something?
    I’m asking you this, becouse i’m working in an e-commerce proyect and I was just looking at your blog and saw this post.
    Well, thank you very much man. I really admire your work.
    Leonardo.

    • Mike Dalisay
      Mike Dalisay says:

      Hi Leonardo, thank you very much for appreciating my works and sharing your thoughts!

      I think using PHP session is a faster and lighter way to handle cart items because it reduces your server load/work. It doesn’t have to do lots of extra queries like INSERT and DELETE.

      But if your project requires tracking of what items were added or removed from cart, you should probably use a database.

      Normally, when the user do a ‘check out’ you should save (to the database) all the items from his cart (for purchase history purposes), but unfortunately, this tutorial focuses on retrieving/adding/removing product items from cart.

  2. Ibrahim
    Ibrahim says:

    thank you so much for sharing that great work with us it really helped a lot.
    would it be too much to ask you to modify the code so that costumers can choose the quantity of the product they want please?
    again you have saved me so much time thank you.

    • Mike Dalisay
      Mike Dalisay says:

      You’re welcome @7e859c986b5f02f7f383df73b264cb5d:disqus! If you want to add that feature, you can do that in the Cart.php, add something like:

      on the heading inside the th tags will be “Quantity”

      and inside the loop…

      I hope that will give you a good start!

      • AHAK
        AHAK says:

        Thanks for replying, adding a row in the table for quantity is basic step what about processing it? can you please give code for a new page updateCart.php and mechanism to update quantity of the product. Thank you

  3. Chrissy
    Chrissy says:

    I uploaded the files as is to my hostgator hosted website but when I click on the products page I get an error:

    “Connection error: SQLSTATE[28000] [1045] Access denied for user ‘root’@’localhost’ (using password: NO)Fatal error: Call to a member function prepare() on a non-object in/home/user/public_html/shopping list test files/Products.php on line 33”

    Does anyone know what I need to do to fix this? I’m assuming I need to add in a password or something, but I really have no clue on how to do that.

    Anywho, thanks for the great tutorial! Now I just need to figure out how to make it work.

  4. Sai Ch
    Sai Ch says:

    ( ! ) Notice: Undefined index: cart in C:wampwwwshopcartNavigation.php on line 2
    Call Stack
    #TimeMemoryFunctionLocation
    10.0028138256{main}( )..index.php:0
    20.0064140752include( ‘C:wampwwwshopcartNavigation.php’ )..index.php:16

    every script contains error like ” Notice: Undefined index” plz help me

  5. Gustavo Caso
    Gustavo Caso says:

    I still get confused with $_SESSION . When did you initialize $_SESSION[‘cart’] ? .
    Thanks I know the question might be stupid, but any help is great.

    • Mike Dalisay
      Mike Dalisay says:

      Hi @disqus_VFFRaOd1U2:disqus, please read my answer to other comments.. you can also use this code to the PHP file you’re currently browsing:

      if(!isset($_SESSION[‘cart’])){
      $_SESSION[‘cart’] = array();
      }

    • Mike Dalisay
      Mike Dalisay says:

      Hi guys, it looks like many of you up-voted this comment NOT because of the error on the navigation.php file, but because I missed to include the navigation.php file code on the tutorial above.

      What happend was I accidentally leave out the navigation.php file when I recently updated the tutorial above. No one commented “navigation.php file & code is missing”.

      Next time, I’ll be more careful when updating our tutorial. If you found a bug, please let me know immediately and be descriptive on the problem so I can take action faster. My email address is mike@codeofaninja.com

      I’m very sorry for the confusion. I added the navigation.php code in section 5.2 above, all thanks to @disqus_oA8v8AP1xq:disqus for brining this to my attention.

  6. Sumit Kumar
    Sumit Kumar says:

    hi Ninjazhai
    Grating of the day.
    I hope you fine.
    here my some problem please guide me …
    I m Trying to build Chat app. in my website with Login only unique id ans also store every chat history in my database;i can’t understand how to do please give me some guideline.

    sumit kumar(sumitkasaudhan1@gmail.com)

  7. klodj
    klodj says:

    The code is written very badly! Sessions are not initialized properly!!! And it is very confusing with all those files having same code repeating over and over.. It needs some cleaning because doesn’t work at all. I don’t know why it works in the Demo! Anyway Great Post :P

    • Mike Dalisay
      Mike Dalisay says:

      Hi @127d8a9b05e560a8c5719cba73f10c68:disqus, can you site how sessions should be initialized in this case? And which files have the same code?

      I agree that this code needs some cleaning, optimization and security, because this is not a production-ready code, this is just an example code that can give someone an idea how a shopping cart script can be done and started from scratch.

      I don’t know why it does not work for you, most people find this code working. I’m a little confused by your comment, you said this is not working but you also said this is a great post?

  8. kring
    kring says:

    are you still here?? :D i tried this code but the product name and price wont display. only the table. i checked my variables and index and it’s ok. why oh why?? :D

    btw, thanks for this one :) it helps me with our assignment.

  9. aya
    aya says:

    hello. i used this code and it only adds the first item in my database. and it replaces the name of the item that is added to number “1”. like 1 is added to your cart and 1 exist in your car(both shows when i add the first item). why is that? btw, thanks for the code :D

  10. Sah
    Sah says:

    Notice: Undefined index: action in E:wampwwwshopping-cart-in-phpProducts.php on line 22 and 26

    getting this error.please help me how to fix this and mostly all are working fine.

  11. Akshay Chauhan
    Akshay Chauhan says:

    i am getting the following errors when i click ‘view products’ and ‘view cart’
    Notice: Undefined variable: con in C:xampphtdocsshoppingcartProducts.php on line 35

    Fatal error: Call to a member function prepare() on a non-object in C:xampphtdocsshoppingcartProducts.phpon line 35

    and

    Notice: Undefined index: action in C:xampphtdocsshoppingcartCart.php on line 20

    Notice: Undefined variable: con in C:xampphtdocsshoppingcartCart.php on line 36

    Fatal error: Call to a member function prepare() on a non-object in C:xampphtdocsshoppingcartCart.php on line 36

    can you please tell me what’s wrong? Thanks

  12. Guest
    Guest says:

    i am getting these errors
    Notice: Undefined variable: con inC:xampphtdocsshoppingcartProducts.php on line35

    Fatal error: Call to a member function prepare() on a non-object in C:xampphtdocsshoppingcartProducts.phpon line 35

    please help

  13. Cheenu Meenu
    Cheenu Meenu says:

    ” Notice: Undefined variable: conprepare in E:STUDY ROOMwampwwwshopping cartproducts.php on line 35 ”

    Fatal error: Function name must be a string in E:STUDY ROOMwampwwwshopping cartproducts.php on line 35

    please sir give me the answer of these errors what can i do?

  14. Ng Tracy
    Ng Tracy says:

    Hi, I found this error:

    In view Product:
    Notice: Undefined index: action in C:xampphtdocssampleProducts.php on line 22
    Notice: Undefined index: action in C:xampphtdocssampleProducts.php on line 26

    In View Cart:
    Notice: Undefined index: action in C:xampphtdocssampleCart.php on line 20

    and view cart shows (1) instead there are no product inside.

    Please help me…

  15. Ng Tracy
    Ng Tracy says:

    Hi,

    I got problem with the

    1. Home page it shows

    Notice: Undefined index: cart in C:xampphtdocssampleNavigation.php on line 2

    2. Product Page it shows

    Notice: Undefined index: cart in C:xampphtdocssampleNavigation.php on line 2

    Notice: Undefined index: action in C:xampphtdocssampleProducts.php on line 22

    Notice: Undefined index: action in C:xampphtdocssampleProducts.php on line 26

    3. Shopping Cart Page shows

    Notice: Undefined index: action in C:xampphtdocssampleCart.php on line 20

    Please help me..

  16. AN
    AN says:

    Congratulations first of all for your codes , I did download your Code which is above , but on my machine when i want to run it , it says Demo is not available , shall i understand in that zip files is not the full project ? can u help me with that please ?!

  17. fsdm
    fsdm says:

    hi, when i add my products to the cart the cart count on products page increase, but when i click ‘view cart’ it says ‘No products found in your cart. :(‘ ?? how to resolve? tq

  18. gino
    gino says:

    i got this problems:

    Fatal error: Call to undefined method mysqli_stmt::rowCount() in C:wampwwwshoppingcartoriginalProducts.php on line 40

    even those wampserver php extention php_pdo_mysql is enable.

  19. Mystro Odei
    Mystro Odei says:

    hi it seems u didnt add the connection file to the zip file so some of the functions are not working. pls check that and by the way this is awesome work bigups.

  20. Ayane
    Ayane says:

    Can somebody tell me what tags and variables should i change in Products.php if im using this table, im confused due to variables using same names and dont know where exacly i should or shouldnt change the original variables for mine.

    CREATE TABLE Articulos(
    OID_A SMALLINT NOT NULL,
    Descripcion VARCHAR(200),
    Precio NUMBER(6,2),
    PRIMARY KEY(OID_A)
    ) ;

    OID_A instead of ‘id’
    Descripcion instead of ‘name’
    precio instead of ‘price’

    thnx

  21. AHAK
    AHAK says:

    Hello Mike, I love your work and you are doing a very noble work by teaching people like me, without any charges and stuff.

    I had been looking for a mentor to teach me how to write a shopping cart from scratch. Then I stumbled upon your Shopping Cart code and it is great. Now I finally know how to do it. I can’t thank you enough but I have a really urgent request, can you please explain to me how I can add Quantity to shopping cart? like oscommerce where you can update the quantity.

    I will be desperately waiting for your reply. Thank you

  22. Tom
    Tom says:

    Hi,

    Great job. I repaired some rows and your cart is working. :)

    some repair:
    // require “libs/DbConnect.php”;
    include(“libs/DbConnect.php”);

    – Products.php and other files the same as:

    $query = “SELECT id, name, price FROM products”;
    $rst = myQuery($query);
    // $stmt = $con->prepare( $query );
    // $stmt->execute();

    $num = mysql_num_rows($rst);

    // $num = $stmt->rowCount();

    if($num>0){
    echo “”;//start table

    // our table heading
    echo “”;
    echo “Product Name”;
    echo “Price (USD)”;
    echo “Action”;
    echo “”;

    while ($row = mysql_fetch_array($rst)) { // while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {

    -db_connect:

    function myQuery($qry){
    $con = mysql_connect(“localhost”,”db”,”pass”);
    if(!$con)
    return false;
    $db = mysql_select_db(“name”,$con);
    if(!$db)
    return false;

    mysql_query(“SET NAMES UTF8”);
    $rst = mysql_query($qry);
    mysql_close($con);
    return $rst;
    }

    thank’s your job

    Yours,
    Tom

  23. joaozinho20
    joaozinho20 says:

    Hey bro.
    That works just fine if you are showing the data of 4-5 produts, but more than that the webpage just goes down and down …
    Do you have any tuturial in how to show like until 5th product and then we can go to another page?
    Like pagination through the Cart …
    Thanks and good night

    • Jeremy
      Jeremy says:

      I’d strongly recommend you do not save against a userid in the form of cookies, it’s a really bad idea if you aren’t encrypting your data and enforcing encryption.

      Use a randomly generated cart/session id for that purpose it’s really I hate to be blunt but it’s a massive security hole.

  24. Jeremy Smith
    Jeremy Smith says:

    Words can’t express how greatful I am for the work and the articles you ;post, had some troubles with doing somethings but your articles as per usual hit the hammer right on the head. They are a great way for expanding upon later too!

    • ninjazhai
      ninjazhai says:

      Hello @disqus_Tkg3Hukomt:disqus, thanks for the kind words! Please don’t hesitate to share your comments regarding any article here so that it will keep on improving with the help of people like you! Thanks!

  25. Jeremy
    Jeremy says:

    Without wanting to cause any offence it does create a little bit of traffic between the client and the server, since with sessions you have to have a file on the server and the clients browser (cookie), your real best bet’s to use pure cookies, though with the likes of bandwidth increasing can be done of course using the above.

  26. Jeremy
    Jeremy says:

    Also sorry I could not put this into my first post about why you should not use sessions, if there was a disk failure or for some reason someone was to remove all sessions from the sessions location (defined in the php.ini file) then the person viewing the cart all items would disappear, with the earlier example where someone was to remove the cookie files from the servers file system using just cookies and not sessions they wouldn’t disappear.

    The above’s probably the most critical reason really not to use sessions, but as tutorials go, this is a great potential example :)

    • ninjazhai
      ninjazhai says:

      Hello @Jeremy, you got some good points there, I really appreciate your effort to improve this post! Your comments are well detailed to be a starting point for new development and contains true arguments about the subject.

      WooCommerce was using PHP sessions for cart data before, but last year they changed it and are now using cookies. I think that’s also a big example and reason why we have to use cookies for storing cart data. See their version 2.0.0 change log here http://wordpress.org/plugins/woocommerce/changelog/

      I will have to create another post on how to use cookies to store cart data. Thanks again for bringing this to my attention!

      But still, as you said, the tutorial above is a great potential example for understanding how shopping carts work before, and still a good example for low traffic shopping website.

      • Jeremy Smith
        Jeremy Smith says:

        I believe in improving peoples skill sets no matter what when it comes to ecommerce, I mean there’s always multiple ways of doing various things and having a background knowledge on how mysql works in a technical sense I know people would love to see.

        Of course I’d be honoured to help anyone that wants it or whatever, thank you so much for saying that I really appreciate it! Take care of yourself :)

      • Jeremy Smith
        Jeremy Smith says:

        To be honest, cookies or sessions would be fair enough to use on a second thought actually, mainly because if there was such an error (I think I said on the serverside, either hard drive fail or whatever) you’d not be able to see anything anyway.

        Be interesting to see what the pitfalls are for either.

  27. Joe Koder
    Joe Koder says:

    If you turn up the PDO connection error reporting you will see you have a problem with a query being run on an empty cart. on line 40 of Cart.php. To see the error, add this to your DB connection:

    $con->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    The problem is when there are no items in the cart, a bad query is sent to the DB and causes an error that you never know about with the existing code.

    This is the actual query sent with no cart items:
    SELECT id, name, price FROM products WHERE id IN ()

    Since the cart is empty, a call to the database for products should not be made.

    Here is the simple fix:

    Cart.php: Change line 27
    FROM

    if(isset($_SESSION[‘cart’])){

    TO

    if(!empty($_SESSION[‘cart’])) {

  28. Carl
    Carl says:

    Notice: Undefined variable: con inC:xampphtdocsEcommersProducts.php on line 37

    Fatal error: Call to a member function prepare() on a non-object in C:xampphtdocsEcommersProducts.php on line 37

    Can you help me to fix this problem I really want to see the output of it too and Thanks for the help in my other project it really help me alot

  29. Louis Blais
    Louis Blais says:

    Hello, This is a great script and I have paid 6.99 for your work (it Worth it). But I got something wrong: Warning: array_key_exists() expects parameter 2 to be array, null given… …on line 56 ( I got this error when I open products.php for the first time.
    Also you should think to Add a pagination in this code.
    Cart price total should appear next to the icon.
    I know i’m late to post in this thread, but I hope you’ll read it!

    • ninjazhai
      ninjazhai says:

      Hi Louis Blais, thanks for downloading our code! Regarding your issue, you can try to add the code below before the while loop:

      if(!isset($_SESSION[‘cart’])){
      $_SESSION[‘cart’]=array();
      }

      Thanks also for all your suggestion, I’ll work on that and you’ll get the free update! :D

    • ninjazhai
      ninjazhai says:

      Hello @louisblais:disqus, thanks for purchasing the code and kind words! Did you receive an email update on this source code? I have fixed any possible issues on the latest update.

  30. saishyam
    saishyam says:

    i am getting this error pls help:

    Fatal error: Call to undefined method mysqli_stmt::rowCount() in D:xampphtdocsproducts.php on line 28

    Notice: Undefined index: cart_items in D:xampphtdocscart.php on line 22

  31. Charles Harris
    Charles Harris says:

    Mike ?

    Does your “downloadable” version have more functionality past the checkout stage? – I clicked checkout on your demo version and nothing happens. I need something solid and simple like this to integrate into a existing portal but need the checkout function to email the buyer and the owner of the store an email with order info and place the order into a separate table for financial tasks.. where can i view the full demo or is this it ?

    Regards
    CH (Sam)

    • ninjazhai
      ninjazhai says:

      Hello Charles,

      It doesn’t have more functionality past the checkout stage. The demo is as is.

      What I’m currently working on is the admin section for products and its login script. More features will come but not yet on the online payment part for now.

  32. sameena banu
    sameena banu says:

    hii,
    thanx for the code..it is really awesome .but i need to add the items in the cart to the database and also the code for checkout..i will be really greatfull if you could help me …plzzz

  33. Judy Ann
    Judy Ann says:

    hi.. i have a question about the codes…

    you know Mr/Mss.programmer I copy all the given steps but why thers an error..

    my error is “Fatal error: Call to a member function prepare() on a non-object in” what should i do??

    can you please help me for this??

  34. maehem
    maehem says:

    hi, i’m maehem… my problem is that i keep on getting an error of “undefined index: cart” in navigation.php and cart.php…… pls help………

  35. Eric Wunderlich
    Eric Wunderlich says:

    Hi, it’s a nice code you have here, i just have a problem, when i put it in my server and tried to enter in products.php, an error saying Warning: session_start() [function.session-start]: Cannot send session cookie – headers already sent by (output started at /home/huntingd/public_html/products.php:9) in/home/huntingd/public_html/products.php on line 10 i dont know what i going on there

    • ninjazhai
      ninjazhai says:

      Yes it works now @Dean1984, please check out the LEVEL 2 live demo above. But if you’re interested in more features, the LEVEL 3 source code is worth checking out!

    • ninjazhai
      ninjazhai says:

      Hello Dean, you’re welcome! Thanks for the interest, I’m releasing a new update on the third or fourth week of March 2015, with the Level 3 source code (admin, user features, and more.)…

        • ninjazhai
          ninjazhai says:

          Hello @disqus_NxELTP5icu:disqus and @ashleydeannaplata:disqus, did you receive the update notification (via email) on the LEVEL 2 source code? Also, LEVEL 3 source code is now available, you can check it out on the article above. :)

          • ninjazhai
            ninjazhai says:

            Thank you for downloading the code! Please see above (after the LEVEL 3 features table in section 7.4) for a simple configuration needed when you install the LEVEL 3 source code. Chat me up if you encounter any other issues, thanks again!

      • AshleyDeanna Plata
        AshleyDeanna Plata says:

        Hi there! Do you have codes for checkout?
        I bought your level-2 source code and it was so good, very big help for me. It was worth it. Thank you very much!

  36. SQL Injection Vulnerability
    SQL Injection Vulnerability says:

    Hey, you got a giant SQL injection vulnerability in your tutorial code, which allows attackers to execute arbitrary SQL commands on the database.

    The way you construct your SQL queries is NOT SAFE. Do not use this code until it is fixed. You should NEVER stitch together SQL queries like this. ALWAYS use prepared statements and parameter binding.

    The keyword is “SQL Injection” and there’s plenty resources on the web.

    • ninjazhai
      ninjazhai says:

      Hello there, first of all, I really appreciate your comment and I wanna thank you for bringing this to my attention, I quickly fixed the issue, I found the vulnerability in the search.php file.

      Here is the solution, please change the query code in search.php, find this part of the code:


      $query = "SELECT id, name, price, category_id FROM products WHERE name LIKE "%{$search_term}%" ORDER BY name LIMIT {$from_record_num}, {$records_per_page}";
      $stmt = $con->prepare( $query );
      $stmt->execute();

      …and then CHANGE IT to this one:


      $query = "SELECT id, name, price, category_id FROM products WHERE name LIKE ? ORDER BY name LIMIT {$from_record_num}, {$records_per_page}";
      $stmt = $con->prepare($query);
      $search_term = "%{$search_term}%";
      $stmt->bindParam(1, $search_term);
      $stmt->execute();

      I sent an email update to those who downloaded the source code.

      • SQL Injection Vulnerability
        SQL Injection Vulnerability says:

        This is the correct approach, but you’ll need to fix each occurrence.

        The line

        $query = “SELECT id, name, price FROM products WHERE id IN ({$ids}) ORDER BY name”;

        is still exploitable. There may be more, I stopped after this one.

        Security holes like this in a shop system are more than scary – one could change prices and place orders. I think I’d go for negative prices.. ;-)

        • ninjazhai
          ninjazhai says:

          Hi there, oh yes I also saw this one coming, I just fixed the more obvious one first, I’m gonna send another update. And yes, the negative prices when you selected a negative quantity, I’m fixing that too… Thanks again!

  37. ninjazhai
    ninjazhai says:

    Hello @AHAK, sorry for the late reply, I just read your comment, do you still need this feature? I believe it’s included on our code update above that you can download. But thanks for the kind words!

  38. winry
    winry says:

    The source codes in this page is NOT for you if:
    —-You are an already an expert in PHP & MySQL programming.
    I like this reason though,. HAhaha XD.

  39. ravinder
    ravinder says:

    hey mike my name is ravinder from india iam using same sessions for wishlist but i want to store the wishlist data into database table with user login can you explain please…. the code wil be shown above

  40. Sorgi
    Sorgi says:

    Hey I just bought the package, It keeps saying that;Notice: Undefined variable: con in C:UsersUserDesktopphpthinghtdocspaypalcartcart.php on line 45

    Fatal error: Call to a member function prepare() on null in C:UsersUserDesktopphpthinghtdocspaypalcartcart.php on line 45

    Notice: Undefined variable: con in products.php on line 25

    Fatal error: Call to a member function prepare() on null in
    products.php on line 25

  41. Josh Dunn
    Josh Dunn says:

    Hi, what a great tutorial. I bought this a few days ago and have already learnt loads! Thankyou so much! I have one question, I am trying to embed this in to a seperate application and it works fine, but the app already has a login section and when different users log in, I want to save the items stored in the cart to their user? Is this possible?

    Thanks

  42. Victor
    Victor says:

    Hello, I am looking to buy the level 3 tutorial for PHP but was wondering if you knew if I would be able to make something that uses logic.
    This will be used to make a job calculator where someone would just enter lengths and the rest will need be calculated and turned into exact parts.
    Thank you for your time,

  43. Flying Squid
    Flying Squid says:

    Hi, Thanks for this tutorial it is amazing. This works great on my local wampserver, but not when I upload my site to justhost server, as then when I click on the cart to view cart items only my navbar appears, no footer and no cart with cart contents! I can still view the product page and add items to the cart, but I cannot view the cart and the total price. Please advise if there is something different I should be doing when uploading it to an online server? My code mirrors yours but with my own navbar and footer..

    Built the site in bootstrap and rather new to shopping carts

    Many thanks

  44. DoublePrince
    DoublePrince says:

    Hey Mike, my name is Martin, a computer science student in Nigeria. I have been visiting many sites checking for ways to learn how to use sessions and cookies and how to know where best to apply them and it seems to me you have really broken it down to my level. Thanks a lot. Maybe when i become as advanced as yourself i can be better able to handle using sessions without disrupting or tampering with server response time, page size and other important stuffs experts like yourself put into consideration for better website performance. Thanks once again.

  45. Mike Dalisay
    Mike Dalisay says:

    Felix, first of all, thank you for your feedback, I appreciate it!

    I did not purposely leave out the navigation.php file on this tutorial. As you can see in the comments, there were errors on that very file, which means it was previously included in this tutorial.

    Other version of the tutorial above has navigation.php file, see https://www.codeofaninja.com/2015/08/simple-php-mysql-shopping-cart-tutorial.html

    What happend was I accidentally leave out the navigation.php file when I updated the tutorial above. No one commented “navigation.php file & code is missing”. You are the only one who did it, so I thank you so much.

    Another note, I reply faster in the email, usually within 24 hours due to dozens of work emails I receive everyday. I still thank you for using our free tutorial above. Sorry for not replying to your comment instantly.

    I added the navigation.php file on section 5.2 above. In exchange of your effort to find a bug in this tutorial, I can send you the source code if you still need it. Send a request to my email mike@codeofaninja.com

    Again thank you for bringing this to my attention.

  46. madhav
    madhav says:

    Fatal error: Call to undefined method Product::readByIds() in C:xampphtdocsphp-shopping-cart-using-sessions-level-1cart.php on line 51 ….can u please say ow to solve it

  47. 「 Knovosh 」
    「 Knovosh 」 says:

    Hello Im Knovosh, Im wondering if i can disable the image functions, when a user clicks the image the items details will appear how can i disable that …. I just want something when i click the image nothing will happen, based on your codes how can i do that badly needed

  48. Mr Krabs
    Mr Krabs says:

    Hello I do not know if the mistake comes from me or from them.
    I did everything after instruction and with me comes constantly the following error:
    Parse error: syntax error, unexpected ‘public’ (T_PUBLIC), expecting end of file in C:xampphtdocsshop_cart_sessions_1objectsproduct.php on line 52

    can you maybe help me because it is very important to me.
    Thank you.

    here is my code:
    https://mega.nz/#!GTww1ArZ!WpYMbGW8m4m5gaLv82wLr19eZhoxo4q6rLG9ZOGlCuk

  49. Mike Dalisay
    Mike Dalisay says:

    Hi @krishnan_ramaswami:disqus, the screenshot does not look like our tutorial above. But the error says you have undefined variables in your read_orders_template.php, make sure you have values for those variables or use the isset() function to check if the values was set.

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