using System;

using System.Linq;

using System.Net.Http;

using System.Security.Cryptography;

using System.Text;

using System.Text.RegularExpressions;

using System.Web.Configuration;

public class Program

{

    public static void Main()

    {

        string jsonString = @"

{    ""PhoneContact"": 2543234567890,

    ""CouponCode"": ""74HX-AW6ZK--G4XW""

}

        ";

        Console.WriteLine(jsonString);

        jsonString = Regex.Replace(jsonString, @"\s+", String.Empty);

        Console.WriteLine(jsonString);

        Console.WriteLine("");

        Console.WriteLine(GenerateSecurityHash("simplesalt", jsonString));

    }

    private static string GenerateSecurityHash(string salt, string content)

    {

        var bytes = Encoding.UTF8.GetBytes(salt).Concat(Encoding.UTF8.GetBytes(content)).ToArray();

        Console.WriteLine(BitConverter.ToString(bytes));

        return Convert.ToBase64String(SHA512.Create().ComputeHash(bytes));

    }

}