How to detect a proxy

IMS

Hello,

Im tring to learn php, and im wanting to know how to detect if a person is hitting my site from a proxy server or not.

I have this code

$_SERVER['HTTP_FORWARDED']
$_SERVER['HTTP_X_FORWARDED_FOR']
$_SERVER['HTTP_CLIENT_IP']

How to i disply if they are from a proxy or not.

Like displyed on the website
Proxy : No
Proxy Yes

Thanks Mike

IMS

Hello,
I have made this,
But it doesnt work. If i use a proxy or not.
It says No proxy.

<?php
if (getenv(HTTP_X_FORWARDED_FOR)) {
	$ipaddress = getenv (HTTP_X_FORWARDED_FOR);
	$servertype = "Proxy";
	} else {
	$ipaddress = getenv (REMOTE_ADDR);
	$servertype = "No Proxy";
	}
	echo ("$servertype")
	?>

If you all can help. Thanks