stripping from variables

[Anon]

Hello I am trying to get the screen res (height and width) into 2 variables in php.
I am using this code:

$screenwidth="< script language='JavaScript' >document.write(screen.width);< /script >";
$screenheight="< script language='JavaScript' >document.write(screen.height);< /script >";

If I echo out the variables I get the correct numbers 1024 and 768 but if i try to do a compare, i get the actual HTML data that the variables are equal to. How can I strip out the HTML data or make the variables equal to the outcome of the HTML after its processed?

[Anon]

I think you need to think this one through. You are trying to create a server variable with a client side code.
You could just put into the page something like...
<?
if(empty($screenwidth) || empty($screenheight)
{
echo "<script language=javascript>\nwindow.href.location = '$PHP_SELF?screenwidth=' + screenwidth + "&screenheight=' + screen.height;\n</script>";
}
?>
That should refresh it with the variables passed to php. There are some other ways to do it if you get creative.