Check is DNS points to local IP address

gistfile1.cs

public static bool IsLocalhost(string hostNameOrAddress)
{
    if (string.IsNullOrEmpty(hostNameOrAddress))
        return false;
 
    try
    {
        // get host IP addresses
        IPAddress[] hostIPs = Dns.GetHostAddresses(hostNameOrAddress);
        // get local IP addresses
        IPAddress[] localIPs = Dns.GetHostAddresses(Dns.GetHostName());
        // test if any host IP is a loopback IP or is equal to any local IP
        return hostIPs.Any(hostIP => IPAddress.IsLoopback(hostIP) || localIPs.Contains(hostIP));
    }
    catch
    {
        return false;
    }
}