help with shopping cart

rozner

I am trying to build a shopping cart, I want to store the contents of the cart in an array and store that in a session. I understand sessions but just started using arrays somehow I'm having trouble combining the two. I was hoping someone can at least tell me if I'm on the right track here. This is what I have so far:


<?
session_start();

$cart = array();

$_SESSION['shoppingcart'] = $cart;

if (!isset($_SESSION['subtotal'])) {
    $_SESSION['subtotal'] = 0;
    $_SESSION['count'] = 0;
}

$cart[$_SESSION['count']]['PID'] = $_GET['item'];
$cart[$_SESSION['count']]['quantity'] = $_GET['quantity'];

$_SESSION['count']++;

if ($_SESSION['status']=="good") {
    if (count($cart)==NULL) {
        echo "Your shopping cart is empty";

} else {
?>
<table cellpadding=0 cellspacing=0 border=0>
<tr><td>Contents of your shopping cart</td></tr>
<tr><td>&nbsp;</td></tr>
<tr><td>Quantity</td><td>Item</td><td>Price</td></tr>
<?
        include 'functions.php';

    $table = "catalog";


    for ($i=0; $i<count($cart);$i++) {

        $pid = $cart[$i]['PID'];

        $sqlquery = "SELECT * FROM $table WHERE ID = $pid";

        $result = dbconnect($sqlquery);

        echo "<tr><td>" . $cart[$i]['quantity'] . "</td><td>" . mysql_result($result,0,"name") . "</td><td>" . mysql_result($result,0,"price") . "</td></tr>";

        $_SESSION['subtotal'] += mysql_result($result,0,"price");

        mysql_close();
    }
?>
        <tr><td>&nbsp;</td></tr>
        <tr><td>Subtotal</td><td><?=$_SESSION['subtotal'];?></td></tr>
        <tr><td>&nbsp;</td></tr>
        <tr><td><a href="main.php">Shop some more</a></td></tr>
        <tr><td><a href="checkout.php">Check out</a></td></tr>

</table>

<?
    }

} else {
    include 'logon.php';
}


?>

It works fine when I add one item, then when I try to add another, I get all kinds of mysql errors. Thanks for any help anyone can provide. It is very much appreciated

rozner

ok, well no one replied but that's ok I got past that problem. Now I have other problems. Like checking for duplicate entries in an array. Here is a revised version of what I previously posted and this one lets you add any number of different items to the cart. When you try to add another of the same item, results are inconsistent. Usually doesn't work, sometimes adds a blank entry, once in a while works properly. So any suggestions would be very much appreciated. Thanks in advance.

<?
session_start();

if (!isset($_SESSION['shoppingcart'])) {
	$_SESSION['shoppingcart'] = array();
	$_SESSION['count'] = 0;
}

$cart = $_SESSION['shoppingcart'];

$item_exists = false;

for ($i=0; $i<count($cart);$i++) {
	if ($cart[$i]['PID']==$_GET['item']) {
		$item_exists = true;
		$index = $i;
	}
}

if (!$item_exists) {

$cart[$_SESSION['count']]['PID'] = $_GET['item'];
$cart[$_SESSION['count']]['quantity'] = $_GET['quantity'];
} else {

$cart[$index]['quantity']++;
}

$_SESSION['shoppingcart'] = $cart;
$_SESSION['count']++;

if ($_SESSION['status']=="good") {
	if (count($cart)==0) {
		echo "Your shopping cart is empty";

} else {
?>
<table cellpadding=0 cellspacing=0 border=0>
<tr><td colspan=3>Contents of your shopping cart</td></tr>
<tr><td>&nbsp;</td></tr>
<tr><td>Quantity</td><td>Item</td><td>Price</td></tr>
<?
		include 'functions.php';

	$table = "catalog";

	$subtotal = 0;

	for ($i=0; $i<count($cart);$i++) {

		$pid = $cart[$i]['PID'];

		$sqlquery = "SELECT * FROM $table WHERE ID = $pid";

		$result = dbconnect($sqlquery);

		echo "<tr><td>" . $cart[$i]['quantity'] . "</td><td>" . mysql_result($result,0,"name") . "</td><td>" . mysql_result($result,0,"price") . "</td></tr>";

		$subtotal += mysql_result($result,0,"price");

		mysql_close();
	}
?>
		<tr><td>&nbsp;</td></tr>
		<tr><td><b>Subtotal</b></td><td><?=$subtotal;?></td></tr>
		<tr><td>&nbsp;</td></tr>
		<tr><td><a href="main.php">Shop some more</a></td></tr>
		<tr><td><a href="checkout.php">Check out</a></td></tr>

</table>

<?
	}

} else {
	include 'logon.php';
}

?>

rozner

well, once again I've figured out my own stupidity. I was incrementing the count everytime regardless of whether or not an item was added to the array. I finally got this thing working.