using System;

using System.Security.Cryptography;

using System.Text;

public class Program

{

    public static void Main()

    {

        string OAuth = "b19080494f03470cbf5ce0477a88d35f ";

        string dt = DateTime.Now.ToString("yyyddMMhhmmss");

        string txnRefID = "2091827172626455" + DateTime.Now.ToString("yyyyddMMhhmmss");

        string st = ooredooSaltKeyGenerate(OAuth, dt);

        Console.WriteLine( "OAuth : "+ OAuth);

        Console.WriteLine("Key :  "+st);

        Console.WriteLine("refID :  " + txnRefID);

    }

    public static string ooredooSaltKeyGenerate(string OAuth, string dt)

        {

            string oddNum = "";

            string req = "REQBODY={}&SALT="+"&DT=";

​

            for (int i = 1; i <= OAuth.Length; i++)

            {

                if (i % 2 != 0)

                {

                    oddNum += OAuth.Substring(i - 1, 1);

                }

            }

            return GenerateSHA512String(req + oddNum);

        }

​

        public static string GenerateSHA512String(string inputString)

        {

            SHA512 sha512 = SHA512Managed.Create();

            byte[] bytes = Encoding.UTF8.GetBytes(inputString);

            byte[] hash = sha512.ComputeHash(bytes);

            return GetStringFromHash(hash);

        }

​

        private static string GetStringFromHash(byte[] hash)

        {

            StringBuilder result = new StringBuilder();

            for (int i = 0; i < hash.Length; i++)

            {

                result.Append(hash[i].ToString("X2"));

            }

            return result.ToString();

        }

​

}