PHP获取真实的IP地址方法

    function getRealIp(){
        if (isset($_SERVER["HTTP_CLIENT_IP"]) && !empty($_SERVER["HTTP_CLIENT_IP"])) {
            $cip = $_SERVER["HTTP_CLIENT_IP"];
        } elseif (isset($_SERVER["HTTP_X_REAL_IP"]) && !empty($_SERVER["HTTP_X_REAL_IP"])) {
            $cip = $_SERVER["HTTP_X_REAL_IP"];
        } else {
            if (!empty($_SERVER["HTTP_X_FORWARDED_FOR"])) {
                $cip = $_SERVER["HTTP_X_FORWARDED_FOR"];
            } else {
                if (!empty($_SERVER["REMOTE_ADDR"])) {
                    $cip = $_SERVER["REMOTE_ADDR"];
                } else {
                    $cip = '';
                }
            }
        }
        preg_match("/[\d\.]{7,15}/", $cip, $cips);
        $cip = isset($cips[0]) ? $cips[0] : '';
        unset($cips);
        return $cip;
    }