判断用户是否使用代理的PHP代码

<?php/******************************************************* isProxy* check whether client is under Proxy or not* $_SERVER[’HTTP_X_FORWARDED_FOR’] is pivotal here* if client is under Proxy, returns true* if client is not under Proxy, returns false* *****************************************************/ function isProxy(){ return (!empty($_SERVER[’HTTP_X_FORWARDED_FOR’])) ? true : false;}?>