using System;

using System.Text.RegularExpressions;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine(IsValidEmail("matt@pavey.n"));

        Console.WriteLine(IsValidEmail("matt@pavey.net"));

        Console.WriteLine(IsValidEmail("matt@grin.agency"));

        Console.WriteLine(IsValidEmail("matt@grin"));

        Console.WriteLine(IsValidEmail("matt@grin."));

        Console.WriteLine(IsValidEmail("matt@grin.x"));

        Console.WriteLine(IsValidEmail("matt's@gmail.com"));

    }

​

    public static bool IsValidEmail(string Value)

    {

        return Regex.Match(Value, "^[A-Z0-9.'_%+-]+@[A-Z0-9.-]+\\.[A-Z]+$", RegexOptions.IgnoreCase).Success;

    }

}