Menu
[code=php]//function.inc.php
<?php
function writeShoppingCart() {
$cart = $_SESSION[‘cart’];
if (!$cart) {
return ‘<p>You have no items in your shopping basket</p>’;
} else {
// Parse the cart session variable
$items = explode(‘,’,$cart);
return ‘<p>You have <a href=”cart.php”>’.count($items).’ item in your shopping cart</a></p>’;
}
}
function showCart() {
$db=new mysqli(‘localhost’,’root’,”);
if(mysqli_connect_errno())
{
die(‘Connect failed:’.mysqli_connect_error());
}
$db->select_db(‘test’)
or die(‘select_db failed:’.$db->error);
$cart = $_SESSION[‘cart’];
if ($cart) {
$items = explode(‘,’,$cart);
$contents = array();
foreach ($items as $item) {
$contents[$item] = (isset($contents[$item])) ? $contents[$item] + 1 : 1;
}
$output[] = ‘<form action=”cart.php?action=update” method=”post” id=”cart”>’;
$output[] = ‘<table>’;
foreach ($contents as $id=>$qty) {
$query=’SELECT * FROM books WHERE id = ‘.$id;
$result=$db->query($query)
or die(‘query failed’.$db->error);
$row = $result->fetch_assoc();
extract($row);
$output[] = ‘<tr>’;
$output[] = ‘<td>’.$title.’ by ‘.$author.'</td>’;
$output[] = ‘<td>RM’.$price.'</td>’;
$output[] = ‘<td><a href=”cart.php?action=delete&id=’.$id.'”>Remove</a></td>’;
$total += $price;
$output[] = ‘</tr>’;
}
$output[] = ‘</table>’;
$output[] = ‘<p>Grand total: <strong> RM’.$total.'</strong></p>’;
//$output[] = ‘<div><button type=”submit”>Update cart</button></div>’;
$output[] = ‘</form>’;
} else {
$output[] = ‘<p>You shopping cart is empty.</p>’;
}
return join(”,$output);
}
?>
————————————————————-
//cart.php
<?php
// Include functions
require_once(‘inc/functions.inc.php’);
// Start the session
session_start();
// Process actions
$cart = $_SESSION[‘cart’];
$action = $_GET[‘action’];
switch ($action) {
case ‘add’:
if ($cart){
if($cart!=$_GET[‘id’]){
$cart .= ‘,’.$_GET[‘id’];
}
else{
echo “you already order the book!”;
}
}
else{
$cart = $_GET[‘id’];
}
break;
case ‘delete’:
if ($cart) {
$items = explode(‘,’,$cart);
$newcart = ”;
foreach ($items as $item) {
if ($_GET[‘id’] != $item) {
if ($newcart != ”) {
$newcart .= ‘,’.$item;
} else {
$newcart = $item;
}
}
}
$cart = $newcart;
}
break;
}
$_SESSION[‘cart’] = $cart;
?>
<body>
<h1>Your Shopping Cart</h1>
<?php
echo writeShoppingCart();
?>
<h1>You have order the following book</h1>
<?php
echo showCart();
?>
<p><a href=”index.php”>Order More Book</a></p>
</body>
</html>
—————————————————-
//index.php
<?php
// Include functions
require_once(‘inc/functions.inc.php’);
// Start the session
session_start();
?>
<body>
<h1>Your Shopping Cart</h1>
<?php
echo writeShoppingCart();
?>
<h1>Books In Our Store</h1>
<?php
$db=new mysqli(‘localhost’,’root’,”);
if(mysqli_connect_errno())
{
die(‘Connect failed:’.mysqli_connect_error());
}
$db->select_db(‘test’)
or die(‘select_db failed:’.$db->error);
$query=’SELECT * FROM books ORDER BY id’;;
$result=$db->query($query)
or die(‘query failed’.$db->error);
$output[] = ‘<ol>’;
while ($row = $result->fetch_assoc()) {
$output[] = ‘<li>”‘.$row[‘title’].'” by ‘.$row[‘author’].’: RM’.$row[‘price’].'<br /><a href=”cart.php?action=add&id=’.$row[‘id’].'”>Add to cart</a></li>’;
}
$output[] = ‘</ol>’;
echo join(”,$output);
?>
</body>
</html>
—————————
CREATE TABLE books(
id int auto_increament,
title varchar
author varchar
price decimal
PRIMARY KEY(id)
examples:
INSERT INTO books VALUES(1,’ABC’,’kelly’,’25.00′);
INSERT INTO books VALUES(2,’XYZ’,’john’,’80.00′);
my Question:
I am using MySQL+PHP5+IIS
(*NOTE:i just let the user to buy each book for ONE unit only.)
step 1(correct):
when i click “Add to cart”(index.php) for the book “ABC” ,
a message was shown in (cart.php):”You have 1 item in your shopping basket”
when i click the “Add to cart”(index.php) for the book “ABC” AGAIN,
a message shown including:”You have 1 item in your shopping basket” and
“you already order the book!”
step 2(have bugs/error occur):
when i click “when i click “Add to cart”(index.php) for the book “XYZ” ,
a message was shown in (cart.php):”You have 2 item in your shopping basket”
when i click the “Add to cart”(index.php) for the book “ABC” AGAIN,
a message shown including:”You have 3 item in your shopping basket”
(*the item number will continue increase)
what i want is:i hope i can get the message “You have 2 item in your shopping basket”
Also,will shown “you already order the book!” when i try to add the same item again!
The coding part that i suspect make the error occur as below:
case ‘add’:
if ($cart){
if($cart!=$_GET[‘id’]){
$cart .= ‘,’.$_GET[‘id’];
}
else{
echo “you already order the book!”;
}
}
else{
$cart = $_GET[‘id’];
}
—>can anyone help me to edit it?