using System;

using System.Linq;

using System.Text.RegularExpressions;

using System.Security.Cryptography;

using System.Text;

​

namespace myApp

{

    public class Program

    {

        public static void Main(string[] args)

        {

            //Your code goes here           

            Console.WriteLine(Encrypt("4NTDMRLNJPGZRBERDJHDEKVH", "{'EVENT':'SALE','REF_ID':'29082016','SERIAL_NUMBER':'32653912','TERMINAL_ID':'','AMOUNT':'000000100000','CURRENCY_CODE':'704','STAFF_ID':'','ADD_PRINT':'','ADD_DATA':'','ORDER_ID':'','APP':'PAYMENT_STD','MERCHANT_OUTLET_ID':'000000000000000000002','MERCHANT_ID':'000000000000002','CLIENT_ID':'0001'}"));

            Console.WriteLine(Decrypt("4NTDMRLNJPGZRBERDJHDEKVH", "45317454454c52616635303562645030703132303473386f7642354167344e704d4d4b7a4e557448684b2f537069652f716b322f34556b5944774961592b4d4a7448317557626e7667476442536f702b543151685835554e6b4e786d394730397936417151376f6234686b3d"));

        }

        public static string Encrypt(string encryptionKey , string textToEncrypt)

        {

            TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider ();

            tdes.Key = Encoding.ASCII.GetBytes(encryptionKey);

            tdes.IV = new byte[] { 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 };

            byte[]  stringBytes = Encoding.UTF8.GetBytes(textToEncrypt);     

            string  st = Convert.ToBase64String(tdes.CreateEncryptor().TransformFinalBlock(stringBytes ,0, stringBytes.Length));

            byte[]  toBytes = Encoding.ASCII.GetBytes(st);

            string s = BitConverter.ToString(toBytes).Replace("-", "").ToLower ();

            Decrypt(encryptionKey , s);

            return s;

        }

        public static string Decrypt(string encryptionKey , string textToDecrypt) 

        {

            TripleDESCryptoServiceProvider  des = new  TripleDESCryptoServiceProvider ();

            des.Key = Encoding.ASCII.GetBytes(encryptionKey);

            des.IV = new  byte[] { 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 , 0x00 };

            byte[]  fromByte = StringToByteArray(textToDecrypt);

            string  st = Encoding.ASCII.GetString(fromByte);

            byte[]  stringBytes = Convert.FromBase64String(st);

            return  Encoding.ASCII.GetString(des.CreateDecryptor().TransformFinalBlock(stringBytes , 0,stringBytes.Length));

        }

        public static byte[] StringToByteArray(string hex)

        {

            return Enumerable.Range(0, hex.Length)

                .Where(x => x % 2 == 0)

                .Select(x => Convert.ToByte(hex.Substring(x, 2), 16))

                .ToArray();

        }

    }

}