Hi, I'm facing a problem which is can't total up all the subtotal amount. Everytime I add a new product to cart, the total only show the last product that I added into cart. Not only that, when I update the quantity of other product, the total still remain the last product price.


The picture above you can see the total only show the amount 21. Any solution?


<!DOCTYPE html>
<!-- Website template by freewebsitetemplates.com -->
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>Artist Website Template</title>
    <link rel="stylesheet" href="images/css/style.css" type="text/css" charset="utf-8" />    

    <span id="background"></span>
    <div id="page">
        <div id="sidebar">
            <div id="logo">
                <a href="index.html">Welcome <p><em><?php echo $_SESSION['username']?></em></p></a>
            </div> <!-- /#logo -->
            <ul id="navigation">
                <li class="selected"><a href="home.php">Product List</a></li>
                <li><a href="member_list.php">Member List</a></li>
                <li><a href="top10.php">Top 10</a></li>
                <li><a href="Report">Report</a></li>
                <li><a href="logout.php">log out</a></li>
            </ul> <!-- /#navigation -->
            <ul id="connect">
                <li><a href="http://facebook.com/" target="_blank" class="facebook"></a></li>
                <li><a href="http://twitter.com/" target="_blank" class="twitter"></a></li>
                <li><a href="" class="link-us"></a></li>
            </ul> <!-- /#connect -->
            <div class="footer">
                © Copyright © 2011.<br/>
                <a href="index.html">D&W CD Rental Store</a> all rights reserved.
            </div> <!-- /.footer -->
        </div> <!-- /#sidebar -->

        <div id="contents">
        <!-- HTML Codes by Quackit.com -->
<p style="text-align:center;"><span style="font-family:Arial;font-size:19px;font-style:normal;font-weight:normal;text-decoration:none;text-transform:uppercase;color:000000;background-color:ffffff;">Product List</span>
<table class="hovertable">
<tr onmouseover="this.style.backgroundColor='#ffff66';" onmouseout="this.style.backgroundColor='#d4e3e5';">
//determind add action
if(isset($_GET['action']) && ($_GET['action'] == 'add')){
    //determind ID from url
        //determind the value is positive or not
        if($_GET['id']> 0){
            //declare ID as $_GET['ID'] from url
        $id =(int) $_GET['id'] ;

        $query = "SELECT * FROM product WHERE ID = $id";
        $result = mysql_query($query,$con);


            echo'Another copy has been added to cart';
            $_SESSION['cart'][$id] = 1;

            echo'This item has been added to your cart';
//if the action is update in url
elseif(isset($_POST['action']) && ($_POST['action'] =='update')){

    foreach ($_POST['qty'] as $id => $v){
            $qty = (int)$v; 
             if ($qty > 0){
                $_SESSION['cart'][$id] =$qty; 

             if($qty == 0){

    echo'Your cart has been updated';


if($_SESSION['cart']) { //if the cart isn't empty
//show the cart

    //iterate through the cart, the $product_id is the key and $quantity is the value
    foreach($_SESSION['cart'] as $id => $v) { 

        //get the name, description and price from the database - this will depend on your database implementation.
        //use sprintf to make sure that $product_id is inserted into the query as a number - to prevent SQL injection

        $sql = sprintf("SELECT * FROM product WHERE id = %d;",

        $result = mysql_query($sql);

        //Only display the row if there is a product (though there should always be as we have already checked)
        if(mysql_num_rows($result) > 0) {

            //list($Name, $Rent_price, $Category) = mysql_fetch_row($result);
            while($row = mysql_fetch_array($result)){
            $total = 0;
            $line_cost = $_SESSION['cart'][$row['ID']] * $row['Rent_price']; //work out the line cost
            $total =$line_cost;
             //add to the total cost
echo'<form action="cart.php" method="post">
     <input type="hidden" name="action" value="update" />';
            echo '<td>' . $row['ID'] . '</td>';
            //show this information in table cells
            echo '<td>' . $row['Name']. '</td>';
            //along with a 'remove' link next to the quantity - which links to this page, but with an action of remove, and the id of the current product
            echo "<td><input type = \"text\" size=\"3\" name=\"qty[$id]\" value =\"{$_SESSION['cart'][$id]}\"> </td>";
            echo '<td>'.$line_cost.'</td>';

            echo "</tr>";


    //show the total
    echo "<tr>";
    echo "<td colspan=\"3\" align=\"right\">Total</td>";
    echo "<td align=\"left\">$total</td>";
    echo "</tr>";

//otherwise tell the user they have no items in their cart
    echo "You have no items in your shopping cart.";

function productExists($id) {
    //use sprintf to make sure that $product_id is inserted into the query as a number - to prevent SQL injection
    $sql = sprintf("SELECT * FROM product WHERE id = %d;", $id); 

    return mysql_num_rows(mysql_query($sql)) > 0;
    echo "<td colspan=\"3\" align=\"right\"><input type=\"submit\" value=\"update\"></td>";



    </div> <!-- /#contents -->
    </div> <!-- /#page -->

Recommended Answers

All 3 Replies

$total is reset in your loop to 0 at line 120. try moving line 120 outside of your loop (before line 105).

Secondly, you're not adding the $line_cost value to the $total, you're just setting the value of $total to the last value of $line_cost for the last loop. Line 122 should be:
$total =$total + $line_cost;

Lastly, i do not see where you are openning the <TR> tag that is closed at line 143. I suspect you need to add the following before line 124:
echo "<tr>";

$total = SUM($line_cost);

@WetCoastLife : You are awesome!!Thank you..It's really work when I move $total=0; outside of the loop . Appreciated

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