using System;

using System.Text.RegularExpressions;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        string hostName = "test-sr1net-appservice.azurewebsites.net";

        Match match = Regex.Match(hostName, "([^.]+\\.[^.]{1,3}(\\.[^.]{1,3})?)$");

        Console.WriteLine(match.Groups[1].Value);

        hostName = "test-sr1net-appservice.abc.net";

        match = Regex.Match(hostName, "([^.]+\\.[^.]{1,3}(\\.[^.]{1,3})?)$");

        Console.WriteLine(match.Groups[1].Value);

        hostName = "xyz.cloudapp.net";

        match = Regex.Match(hostName, "([^.]+\\.[^.]{1,3}(\\.[^.]{1,3})?)$");

        Console.WriteLine(match.Groups[1].Value);

        hostName = "sr1net.com";

        match = Regex.Match(hostName, "([^.]+\\.[^.]{1,3}(\\.[^.]{1,3})?)$");

        Console.WriteLine(match.Groups[1].Value);

        string a="test-sr1net-appservice.azurewebsites.net";

        bool k=a.EndsWith(".azurewebsites.net");

        Console.WriteLine(k);

    }   

}