Prevent Browsers Caching

Hi everybody,

I’d like to find something that will give viewers an updated page whenever they enter a page. It will be used for current conditions and I want to avoid any caching their browser/server will do. I have found a couple, and try adding:

<meta http-equiv="Pragma" content="no-cache" />
<meta http-equiv="Cache-Control" content="no-cache" />
<meta http-equiv="Expires" content="-1" />

to my meta tags (header.php), but they won’t serve my purpose. I’ve tried Javascript below too:

<script type="text/javascript">
var domain = "mydomain.com"
var str=location.href
var pos=str.indexOf(domain)
if (pos>=12 || pos=-1)
{
document.location.replace("http://www."+domain);
}
</script>

but javascript above doesn’t work properly. And i try again using this:

<?php
header( "Expires: Mon, 20 Dec 1998 01:00:00 GMT" );
header( "Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT" );
header( "Cache-Control: no-cache, must-revalidate" );
header( "Pragma: no-cache" );
?>

but still doesn’t work. Possibility, these codes above is no good for this sort of thing as it’s client-side. So perhaps anybody knows a good server-side script to do this (a php version), include how to use it, please let me know.