如何取得用户的真实IP

如何取得用户的真实IP

PHP代码:--------------------------------------------------------------------------------

<?
function iptype1 () {
if (getenv("HTTP_CLIENT_IP")) {
  return getenv("HTTP_CLIENT_IP");
}
else {
  return "none";
}
}
function iptype2 () {
if (getenv("HTTP_X_FORWARDED_FOR")) {
  return getenv("HTTP_X_FORWARDED_FOR");
}
else {
  return "none";
}
}
function iptype3 () {
if (getenv("REMOTE_ADDR")) {
  return getenv("REMOTE_ADDR");
}
else {
  return "none";
}
}
function ip() {
$ip1 = iptype1();
$ip2 = iptype2();
$ip3 = iptype3();
if (isset($ip1) && $ip1 != "none" && $ip1 != "unknown") {
  return $ip1;
}
elseif (isset($ip2) && $ip2 != "none" && $ip2 != "unknown") {
  return $ip2;
}
elseif (isset($ip3) && $ip3 != "none" && $ip3 != "unknown") {
  return $ip3;
}   
else {
return "none";
}
}

Echo ip();
?>