php获取用户IPv4或IPv6地址的代码_php技巧

function getIP() /*获取客户端IP*/ 
{ 
if (@$_SERVER["HTTP_X_FORWARDED_FOR"]) 
$ip = $_SERVER["HTTP_X_FORWARDED_FOR"]; 
else if (@$_SERVER["HTTP_CLIENT_IP"]) 
$ip = $_SERVER["HTTP_CLIENT_IP"]; 
else if (@$_SERVER["REMOTE_ADDR"]) 
$ip = $_SERVER["REMOTE_ADDR"]; 
else if (@getenv("HTTP_X_FORWARDED_FOR")) 
$ip = getenv("HTTP_X_FORWARDED_FOR"); 
else if (@getenv("HTTP_CLIENT_IP")) 
$ip = getenv("HTTP_CLIENT_IP"); 
else if (@getenv("REMOTE_ADDR")) 
$ip = getenv("REMOTE_ADDR"); 
else 
$ip = "Unknown"; 
return $ip; 
} 
?>