Invalid argument...

Warning: Invalid argument supplied for foreach() in /.******************************/web/wad/sbasket.php on line 196

<?php

session_start ();

include ('connection.php');

// define session variable
$_SESSION['cart'];

//if product exists in command line, add it to cart
@$id = $_GET['prod_id'];

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);
$s = (count($items) > 1) ? 's':'';
return '<p>You have <a href="cart.php"> '.count($items).' item '.$s.' in your shopping basket</a></p>';
}
}

function showCart() {
global $db;
$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) {
$sql = "SELECT * FROM products WHERE prod_id = ".$id." ";
$result = $db->query($sql);
$row = $result->fetch();
extract($row);
$output[] = '<tr>';
$output[] = '<td><a href="cart.php?action=delete&id='.$id.'" class="r">Remove</a></td>';
$output[] = '<td>'.$p_name.'</td>';
$output[] = '<td>&pound;'.$price_wk.'</td>';
$output[] = '<td><input type="text" name="qty '.$id.' "value="'.$qty.'" size="3" maxlength="3" /></td>';
$output[] = "<td>&pound;".($price_wk * $qty)."</td>";
$total += $price_wk * $qty;
$output[] = '</tr>';
}
$output[] = '</table>';
$output[] = '<p>Grand total: <strong>&pound;'.$total.'</strong></p>';
$output[] = '<div><button type="submit">Update cart</button></div>';
$output[] = '</form>';
} else {
$output[] = '<p>You shopping basket is empty.</p>';
}
return join('',$output);
}


//checks if command line has product added
if($id){
//checks if cart is empty & creates it
if(!isset($_SESSION['cart'])){
$_SESSION['cart'] = array();
$_SESSION['items'] = 0;
$_SESSION['total_price'] = '0.00';
}

//cart array contains productid & quantity
if (isset($_SESSION['cart'] [$id] ))
$_SESSION['cart'] [$id]++;
else
$_SESSION['cart'] [$id] = 1;
}

//checks if command line has product updated
if(isset($_POST['update'])){
foreach ($_SESSION['cart'] as $id => $qty){
//value from text box name
if($_POST[$id]=='0')
unset($_SESSION['cart'] [$id]);
else
$_SESSION['cart'] [$id] = $_POST[$id];
}
}
?>



<?php
//displays products
if ($_SESSION['cart']){
echo '<div id="product">';
echo '<h3>My Basket</h3>';
echo '<table width="400" border="0" cellpadding=0 cellspacing=5>';
echo '<form name="userForm" method="post" action="sbasket.php">';
echo '<tr><th width="200" scope="col" align="center">Title</th>';
echo '<th width="100" align="right">Quantity</th>';
echo '<th width="100" align="right">Price</th></tr>';
$_SESSION['total_price'] = '0.00';
$_SESSION['items'] = 0;

//place lines of products in page
foreach ($_SESSION['cart'] as $id => $qty){
$query = 'select * from products where prod_id = '.$id.' ';
$result = mysql_query($query);
if (!$result){
mysql_close($conn);
return -2;
}
$catNo = mysql_num_rows($result);
if ($catNo == 0){
mysql_close($conn);
return 0;
}
$product = array();
$product = mysql_fetch_array($result);

$tprice = $qty*$product['price_wk'];

echo '<tr><td align = "left"><span>';
echo $product['p_name'];
echo '</span></td>';
echo '<td align = "right"><span>';
//name of textbox=prodid and value=qty
echo '<input name="'.$id.'" type="text" size="3" maxlength="3" value="'.$qty.'">';
echo '</span></td>';
echo '<td align = "right"><span>&pound;';
echo $tprice;
echo '</span></td></tr>';

$_SESSION['items'] += $qty;
$_SESSION['total_price'] += $tprice;
}

//starts the update qty proceedure
echo '<input type="hidden" name="update" value=true>';

echo '<tr bgcolor="#999999"><td align="center"><input type="submit" name="Submit" value="Update Shopping Basket"></td><td align = "right"><b>Number of weeks: '.$_SESSION['items'].'</b></td><td align="right"><b>Total Price: &pound;'.$_SESSION['total_price'].'</b></td></tr>';
echo '</form>';
echo '</table>';
echo '</div>';

}else{ //if no product in cart
echo '<div id="information">';
echo '<h3><span>No products in Shopping basket</span></h3>';
echo '<p class="p1"><span>Please login and add products to your shopping basket</span></p>';
echo '</div>';
}


//further options
echo '<div id="product">';
echo '<h3>Further options</h3>';
if(isset($_SESSION['loggedUser'])){
echo '<form name="furForm" method="post" action="finalizeorder.php"><input type="submit" name="Submit" value="Finalize Order"></form>';
}
else{
echo '<form name="furForm" method="post" action="register.php"><input type="submit" name="Submit" value="Please login to finalize your order"></form>';
}
echo '</div>';
?>

What could be wrong with the foreach statement?

 

Change this:

<?php
//displays products
if ($_SESSION['cart']){

Code (markup):

to:

<?php
//displays products
if (isset($_SESSION['cart'])) {

Code (markup):

or even better:

<?php
//displays products
if (isset($_SESSION['cart']) && is_array($_SESSION['cart'])) {

Code (markup):

 

Thank you.

That helped.