using System;

using System.Linq;  

using System.Text ;

using System.IO;

using System.Security.Cryptography;

public class Program

{

     static public string EncodeTo64(string toEncode)

​

    {

​

      byte[] toEncodeAsBytes

​

            = System.Text.ASCIIEncoding.ASCII.GetBytes(toEncode);

​

      string returnValue

​

            = System.Convert.ToBase64String(toEncodeAsBytes);

​

      return returnValue;

​

    }

    public static string Encrypt(string data, string key, string iv)

    {

        //===== data

        var bytes = Encoding.UTF8.GetBytes(data);

        //===== AES provider

        var provider = new AesCryptoServiceProvider();

        provider.Mode = CipherMode.CBC;

        provider.Key = Encoding.UTF8.GetBytes(key);

        provider.IV = Encoding.UTF8.GetBytes(iv);

        var transform = provider.CreateEncryptor();

        //===== encrypt

        using (var ms = new MemoryStream())

        {

            using (var cs = new CryptoStream(ms, transform, CryptoStreamMode.Write))

            {

                cs.Write(bytes, 0, bytes.Length);

                cs.FlushFinalBlock();

            }

            //===== encrypted data

            var sb = new StringBuilder();

            foreach (var b in ms.ToArray())

            {

                sb.Append(b.ToString("X2"));

            }

            return sb.ToString();

        }

    }

    public static string Decrypt(string hexString, string key, string iv)

    {

        var bytes = Enumerable.Range(0, hexString.Length)

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

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

            .ToArray();

        //===== AES provider

        var provider = new AesCryptoServiceProvider();

        provider.Mode = CipherMode.CBC;

        provider.Key = Encoding.UTF8.GetBytes(key);

        provider.IV = Encoding.UTF8.GetBytes(iv);

        var transform = provider.CreateDecryptor();

        using (var ms = new MemoryStream(bytes))

        {

            using (var cs = new CryptoStream(ms, transform, CryptoStreamMode.Read))

            {

                using (var sr = new StreamReader(cs))

                {

                    cs.Flush();

                    var plainText = sr.ReadToEnd();

                    return plainText;

                }

            }

        }

    }

    public static void Main()

    {

        //working

        var key = "36D65EA1F6A849AF9964E0BAA98096B3";

        var iv = "8E394493F1E54545";

        var encrypted = Encrypt("testing", key, iv);

        Console.WriteLine(encrypted);

        var decrypted = Decrypt(encrypted ,key, iv);

        Console.WriteLine(decrypted);

        //attempting to use a ruby-generated key/iv

        key = "65125495c896b9e73a7a79fd7ed21be034a05596d3c7d0b865fc40a67ccbdd03";

        iv = "4b1e02d778aa1131e0612ff2dc2f9c49";

        encrypted = Encrypt("testing", key, iv);

        Console.WriteLine(encrypted);

        decrypted = Decrypt(encrypted ,key, iv);

        Console.WriteLine(decrypted);

    }

}