using System;

using System.Web;

public class Program

{

    public static void Main()

    {

        var text = "@";

        //UrlEncode

        var enc = HttpUtility.UrlEncode(text);

        Console.WriteLine(enc);

        //UrlDecode

        var dec = HttpUtility.UrlDecode(enc);

        Console.WriteLine(dec);

    }

}