using System;

using System.Linq;

using System.Web;

using System.Configuration;

using System.Security.Cryptography;

using System.Text;

using System.IO;

​

public class Program

{

    public static void Main()

    {

            // TODO: Get the shared key from the file

            var dummyKey = "bNFtS+duJn+wPjDNU2B0LLoVVhckygAZEmMxfCsDJgg=";

            var key = Convert.FromBase64String(dummyKey);

            //Generate Random Initialization Vector

            var iV = new byte[16];

            RandomNumberGenerator.Create().GetBytes(iV);

            //Create formatted value to be encrypted

            var sb = new StringBuilder();

            var value = sb.Append('4').Append('|').Append(DateTime.Now.ToString()).ToString();

            //Create Pipe char as byte array

            var pipe = new byte[]{Convert.ToByte('|')};

            //Encrypt MemberKey value

            var encryptedMemberKey = EncryptStringToBytes_Aes(value, key, iV);

            //Combine Arrays to prepare for BlockCopy

            var arrays = new byte[][]{iV, pipe, encryptedMemberKey};

            var memberKey = new byte[arrays.Sum(a => a.Length)];

            //Using Combined array, create new byte[] containing the IV, delimiter and encrypted value

            var offset = 0;

            foreach (byte[] array in arrays) {

            System.Buffer.BlockCopy(array, 0, memberKey, offset, array.Length);

            offset += array.Length;

            }

            Console.WriteLine(Convert.ToBase64String(memberKey));

    }

​

    public static byte[] EncryptStringToBytes_Aes(string value, byte[] Key, byte[] IV)

    {

        // Check arguments.

        if (value == null || value.Length <= 0)

            throw new ArgumentNullException("plainText");

        if (Key == null || Key.Length <= 0)

            throw new ArgumentNullException("Key");

        if (IV == null || IV.Length <= 0)

            throw new ArgumentNullException("IV");

        byte[] encrypted;

        // Create an Aes object

        // with the specified key and IV.

        using (Aes aesAlg = Aes.Create())

        {

            aesAlg.Mode = CipherMode.CBC;

            aesAlg.KeySize = 256;

            aesAlg.Key = Key;

            aesAlg.IV = IV;

            aesAlg.Padding = PaddingMode.PKCS7;

            // Create a decrytor to perform the stream transform.

            ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

            // Create the streams used for encryption.

            using (MemoryStream msEncrypt = new MemoryStream())

            {

                using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))

                {

                    using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))

                    {

                        //Write all data to the stream.

                        swEncrypt.Write(value);

                    }

​

                    encrypted = msEncrypt.ToArray();

                }

            }

        }

​

        // Return the encrypted bytes from the memory stream.

        return encrypted;

    }

}