function getIP() {
return isset($_SERVER["HTTP_X_FORWARDED_FOR"])?$_SERVER["HTTP_X_FORWARDED_FOR"]
:(isset($_SERVER["HTTP_CLIENT_IP"])?$_SERVER["HTTP_CLIENT_IP"]
:$_SERVER["REMOTE_ADDR"]);
}
原文：https://www.cnblogs.com/wjm956/p/9285107.html