[PHP] how do I find out which checkbox is checked when form get submit

[Jacky]

Hi all,
Extremely desparate here as I still cannot get my problem sought out, so decided
to post my question again.
Allow me to repeat my question again:
I have a form with the checkbox like this
<form>
<?php
$query="select id from foo";
$result=($query,$con);
while ($row = mysql_fetch_array($result))
     {
print("<input type="checkbox" name="$id" value="on">");
     }
....submit button and stuffs here...
?>
</form>

After I tried check on few checkboxes and submit to next page, at next page, how do I 
check which check box is
checked so that I can get value of the checked one to process to next step?
I did try isset() and empty() to check if variable exist ( as shown below)
and did not work as the result always turn up to be "off"

   if((empty($id))=='true'){
        echo "off";
     }else{
       echo "on";
   }

And I also try
if(isset($id))
{
  ..do echo off here...
}else{
  ...do echo on....
}

And the result is always "off" as well.

Somene advice me to use $http_var_gets btu I could not find it from manaual,
is that the solution I need?
cheers

Jack
[EMAIL PROTECTED]
"There is nothing more rewarding than reaching the goal you set for yourself"