using System;

using System.Security.Cryptography;

using System.Text;

public class Program

{

    public static string CreateMD5(string input)

    {

    // Use input string to calculate MD5 hash

     using (System.Security.Cryptography.MD5 md5 = System.Security.Cryptography.MD5.Create())

     {

        byte[] inputBytes = System.Text.Encoding.ASCII.GetBytes(input);

        byte[] hashBytes = md5.ComputeHash(inputBytes);

​

        // Convert the byte array to hexadecimal string

        StringBuilder sb = new StringBuilder();

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

        {

            sb.Append(hashBytes[i].ToString("X2"));

        }

        return sb.ToString();

         }

    }

    public static void Main()

    {

        var Timestamp = new DateTimeOffset(DateTime.UtcNow).ToUnixTimeSeconds();

        string _key ="03cca83cc915493780058861699711e2";

        string secret = "9c00c36747d14d9e92a8c3c292c1f793a50d78493dd14890acc2f882e85f843d";

                    //  4d1715e032c44b709ef4954ef13e0950

                    //  fb91e9e96f054166b567eec1b170ae2b

        string StringA = "app_key="+_key+"&timestamp=" + Timestamp;

        string temp = StringA + secret;

        string md5 = CreateMD5(temp);

        Console.WriteLine(md5);

    }

}