Undefined variable

[TottoBennington]

Notice: Undefined variable: quantity_row in C:\xampp\htdocs\cart\cart.php on line 12

 

Notice: Undefined index: cart_1 in C:\xampp\htdocs\cart\cart.php on line 12

 

Notice: Undefined index: cart_1 in C:\xampp\htdocs\cart\cart.php on line 30

 

Help me guys

 

<?php 
session_start();

$page = 'index.php';

mysql_connect('localhost','root','')or die(mysql_error());
mysql_select_db('cart') or die(mysql_error());

if (isset ($_GET['add'])){
     $quantity = mysql_query('SELECT id, quantity FROM products WHERE id ='.mysql_real_escape_string( (int)$_GET['add']));
 while($quantity_rows = mysql_fetch_assoc($quantity)) {
     if ($quantity_row['quantity'] != $_SESSION['cart_'.$_GET['add']]) {
	     $_SESSION['cart_'.$_GET['add']] += '1';
	 }
 }

}

function products() {
$get = mysql_query('SELECT id, name, description, price FROM products WHERE quantity > 0 ORDER BY id DESC') or die(mysql_error());
 if (mysql_num_rows($get) == 0) {
     echo 'There are no products to display!';
 } else {
     while ($get_row = mysql_fetch_assoc($get)) {
	     echo '<p>'.$get_row['name']. '<br />' .$get_row['description']. '<br />'.number_format( $get_row['price'], 2) . '<a href="cart.php?add='.  $get_row['id'].'">Add</a></p>';
	 }
 }
}

echo $_SESSION['cart_1'];
?>

[smerny]

while($quantity_rows = mysql_fetch_assoc($quantity)) {

    if ($quantity_row['quantity'] != $_SESSION['cart_'.$_GET['add']])

 

 

 

you initiate quantity_rows and then check quantity_row (no "s")