Javascript countdown not working for php loop - php

Question

Hello i me and a friend have a maffia game. I have a countdown timer code but it only works when i use one timer. But i need to use it in a loop to get more timers in a table. I searched on google but nothing really helped. I saw that i had to use different id's but that didn't work for me. I have little knowledge of javascript.
This are my codes:
While loop:
while($info = mysql_fetch_object($dbres))
{
$j = 0;
$bieding = mysql_fetch_object(mysql_query("SELECT `bedrag` FROM `biedingen` WHERE `veilingid`='{$info->id}' ORDER BY `bedrag` DESC LIMIT 1"));
$tijd = ($info->tijd + $info->duur * 60 * 60 - $time);
echo '<tr>
<td>'.veilingnaam($info->id,1,1).'</td>
<td>'.usernaam($info->veiler,1,1).'</td>
<td>€'.getal($bieding->bedrag).'</td>
<td><div id="teller'.$j.'"></div></td>
</tr>';
}
Javascript part:
<script type="text/javascript">
var seconds = <?= ($tijd+1) ?>;
var countdown = document.all? document.all["teller<?= $j?>"] : document.getElementById? document.getElementById("teller<?= $j?>") : "";
var woord = "seconden";
function display()
{
seconds=seconds-1;
if(seconds==1){ woord="seconde"; }
if(seconds==0){ woord="seconden"; }
if(seconds<0)
{
self.location.replace(self.location);
}
else
{
if (countdown)
{
countdown.innerHTML=seconds+" "+woord;
setTimeout('display()',1000);
}
}
}
display();
</script>

Answer 1

Your while loop goes through table rows in a DB, but your JavaScript code is not part of that loop. That means you generate a HTML table for each row, but then you create <script>...</script> which includes $tijd/$j only for the last row (assuming that your while executes before the script is added to the page.
Possible workarounds:
Add a jQuery's selector, something like $("div.teller").each(function(){...}); and in that function create a timer and/or any other JavaScript code you need associated with that div.Note that this requires your div to get a CSS class "teller".
Create all JavaScript code that is needed for each DB's table row inside the PHP's while loop, but this would probably get really messy.
Also, I advise you to take a look at JavaScript's setInterval(), since it is more appropriate than setTimeout() for what you want to do.
Another thing to consider: all your timers would have a one second tick. It seems to me that it is better to have a single timer and just keep numbers of seconds (whatever that might be) in a JavaScript array (this one is easily created in PHP's while loop).
Edit: Here is one way to do this:
$data = array();
while($info = mysql_fetch_object($dbres))
{
... /* your current code */
$data[] = "{ id: 'teller$j', seconds: $tijd }";
}
$data = "[ ".implode(", ", $data)." ]";
Now, create your JavaScript code outside of the loop:
<script type="text/javascript">
var data = <?php echo $data; ?>; // It is not advisable to use <?= ... ?>
// Get references to divs via saved ids (seconds are already saved
for (i = 0; i < data.length; i++)
data.div = document.getElementById(data.id); // No need for document.all; IE supports getElementById since version 5.5
...
</script>
Now, adapt display() to work with the elements of your data array.