Get the IP address of the current user

getUserIP.php

private function getUserIP()
{
  $client  = @$_SERVER['HTTP_CLIENT_IP'];
  $forward = @$_SERVER['HTTP_X_FORWARDED_FOR'];
  $remote  = $_SERVER['REMOTE_ADDR'];

  if(filter_var($client, FILTER_VALIDATE_IP)) {
    $ip = $client;
  }
  elseif(filter_var($forward, FILTER_VALIDATE_IP)) {
    $ip = $forward;
  }
  else {
    $ip = $remote;
  }

  return $ip;
}