求获取客户端真实ip跳转相应网址的PHP源代码

function get_real_ip(){
$ip=false;
if(!empty($_SERVER["HTTP_CLIENT_IP"])){
$ip = $_SERVER["HTTP_CLIENT_IP"];
}
if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
$ips = explode (", ", $_SERVER['HTTP_X_FORWARDED_FOR']);
if ($ip) { array_unshift($ips, $ip); $ip = FALSE; }
for ($i = 0; $i < count($ips); $i++) {
if (!eregi ("^(10|172\.16|192\.168)\.", $ips[$i])) {
$ip = $ips[$i];
break;
}
}
}
return ($ip ? $ip : $_SERVER['REMOTE_ADDR']);
}
$ip=get_real_ip();
if($ip=='218.75.148.100')header('Location: http://www.A.com/');

else header('Location: http://www.B.com/');