PHP/MYSQL. Updating multiple rows failing in the `for loop`

I have following HTML table:

<form method="post" action="update-table.php">
    <table class="table-data" style="width: 960px;">
        <thead>
            <tr>
                <td class="sorting" rowspan="1" colspan="1" style="width: 193px;">ID</td>
                <td class="sorting" rowspan="1" colspan="1" style="width: 54px;">Live</td>

            </tr>
        </thead>
        <tbody>
            <tr class="odd">
                <td class="nth-1"><input type="text" value="12" name="id"></td>
                <td class="nth-2"><input type="checkbox" checked="checked" name="live"></td>

            </tr>
            <tr class="even">
                <td class="nth-1"><input type="text" value="11" name="id"></td>
                <td class="nth-2"><input type="checkbox" checked="checked" name="live"></td>

            </tr>
            <tr class="odd">
                <td class="nth-1"><input type="text" value="10" name="id"></td>
                <td class="nth-2"><input type="checkbox" checked="checked" name="live"></td>

            </tr>
        </tbody>
    </table>
<input type="submit" />

and I'm trying to update live values accordingly to the ids with this file:

<?php
# update
session_name('users');
session_set_cookie_params(2*7*24*60*60);
session_start();

define('INCLUDE_CHECK',true);

require 'connect.php';
require 'functions.php';

if(!$_SESSION['id']) {
    header ("Location: index.php"); 
}


        //Function to sanitize values received from the form. Prevents SQL injection
        function clean($str) {
            $str = @trim($str);
            if(get_magic_quotes_gpc()) {
                $str = stripslashes($str);
            }
            return mysql_real_escape_string($str);
        }

        //Sanitize the POST values
        $id = cle开发者_Go百科an($_POST['id']);
        //$usr2 = $_SESSION['usr'];
        $live = (isset($_POST['live']))?1:0;
        //$updated = date("F j, Y, g:i a",time()+60*60);

        //Create INSERT query
        foreach ($display_order as $id => $live) {
            $sql = "UPDATE news SET display_order = $live WHERE id = $id";
            $result = mysql_query($sql);

            if($result) {
                //header("location: notes.php");
                //exit();
                print_r($sql);
                print_r($display_order);
            }else {
                die("Query failed");

            }
        }
?>

But I'm getting an error:

Warning: Invalid argument supplied for foreach() in C:\Documents and Settings\USER\Desktop\Dropbox\wamp_at_work\update-table.php on line 33

Line 33 is: foreach ($display_order as $id => $live) {

What the problem? Any suggestions much appreciated.

The problem is that you're duplicating the 'name' attributes of the input elements. What you want to do is send arrays back to the server, ie:

Updated with extended answer:

<?php

$inp_orders = !empty($_POST['live']) ? $_POST['live'] : array();

// proccess post
if ($inp_orders)
{
        foreach ($inp_orders as $id => $live) {
            $id = (int) $id;
            $live = (bool) $live;

            // update orders
            $sql = "UPDATE news SET display_order = $live WHERE id = $id";
            $result = mysql_query($sql);

                if($result) {
                    echo 'News updated';
                }else {
                    die("Query failed");
                }
        }
}

// get orders from db
$res = mysql_select("SELECT * FROM news");
$view_orders = array();

    while ($row = mysql_fetch_assoc($res))
    {
        $view_orders['id'] = $row['id'];
        $view_orders['live'] = $row['live'];
    }

?>


<form method="post" action="">
    <table class="table-data" style="width: 960px;">
        <thead>
            <tr>
                <td class="sorting" rowspan="1" colspan="1" style="width: 193px;">ID</td>
                <td class="sorting" rowspan="1" colspan="1" style="width: 54px;">Live</td>

            </tr>
        </thead>
        <tbody>
                    <?php foreach ($view_orders as $order): $id = (int) $order['id']; $odd = true; ?>
                    <tr class="<?php echo $odd ? 'odd' : 'even' ?>">
                        <td class="nth-1"><?php echo $id ?></td>
                        <td class="nth-2"><input type="checkbox" <?php echo $order['live'] ? 'checked="checked"' : ''  ?> name="live[<?php echo $id ?>]" /></td>
                    </tr>
                    <?php $odd = $odd ? false : true; endforeach; ?>
        </tbody>
    </table>
    <input type="submit" />
</form>

I'm going to assume people can not change the ID. So do this:

<td class="nth-2">
  <input type="hidden" name="live[12]" value="0">
  <input type="checkbox" name="live[12]" value="1" checked>
</td>

That will get you an array called $_POST['live'] with either 0 or 1 in it depending on if they clicked it.

The hidden field is because if they don't click it nothing at all is sent, which can be more difficult to parse, so first I send a 0, then overwrite it if the checkbox is checked.

If people can change the ID you'll need to modify it a bit. Leave a comment if so.