using System;

using System.Text.RegularExpressions;

​

public class Program

{

    public static void Main()

    {

        var CardHolderNameRegExPattern = @"^([a-zA-Z]+\s)+[a-zA-Z]+$";

        var cardHolderName = "John Doe2";

        Console.WriteLine("Result: {0}", Regex.IsMatch(cardHolderName, CardHolderNameRegExPattern));

    }

}