How can we get the IP address of the client?

to get the correct IP address of the user

function getUserIpAddr(){
    if(!empty($_SERVER['HTTP_CLIENT_IP'])){
        //ip from share internet
        $ip = $_SERVER['HTTP_CLIENT_IP'];
    }elseif(!empty($_SERVER['HTTP_X_FORWARDED_FOR'])){
        //ip pass from proxy
        $ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
    }else{
        $ip = $_SERVER['REMOTE_ADDR'];
    }
    return $ip;
}
echo 'User Real IP - '.getUserIpAddr();