using System;

using System.Web;

public class Program

{

    public static void Main()

    {

        string testString = "VGVzdDEgLSA6Ojo7OzsnJ34hQCMkJV4mKigpXytgLT1bXXt9Iid8XDw+LC4/Ly50eHQ=";

        testString = "Test1 - :::;;;''~!@#$%^&*()_+`-=[]{}\"'|\\<>,.?/.txt"; // Test1 - :::;;;''~!@#$%^&*()_+`-=[]{}"'|\<>,.?/.txt

        Console.WriteLine("UrlEncode: " + System.Web.HttpUtility.UrlEncode(testString));

        Console.WriteLine("EscapeUriString: " + Uri.EscapeUriString(testString));

        Console.WriteLine("EscapeDataString: " + Uri.EscapeDataString(testString));

        Console.WriteLine("EscapeDataReplace: " + Uri.EscapeDataString(testString).Replace("%20", "+"));    

        Console.WriteLine("HtmlEncode: " + System.Web.HttpUtility.HtmlEncode(testString));

        Console.WriteLine("UrlPathEncode: " + System.Web.HttpUtility.UrlPathEncode(testString));

        //.Net 4.0+

        //Console.WriteLine("WebUtility.HtmlEncode: " + WebUtility.HtmlEncode(testString));

        //.Net 4.5+

        //Console.WriteLine("WebUtility.UrlEncode: " + WebUtility.UrlEncode(testString));                                                                                          

    }

}