php 取得使用者ip

//取得使用者ip
if(!empty($_SERVER['HTTP_CLIENT_IP'])){
  $i_userip = $_SERVER['HTTP_CLIENT_IP'];
}else if(!empty($_SERVER['HTTP_X_FORWARDED_FOR'])){
 $i_userip = $_SERVER['HTTP_X_FORWARDED_FOR'];
}else{
 $i_userip= $_SERVER['REMOTE_ADDR'];
}