using System;

using System.Security.Cryptography;

//using System.Security.Cryptography.Aes;

using System.Text;

using System.IO;

​

public class Program

{

    public static String AES_encrypt(String Input, String AES_Key, String AES_IV)

    {

        // Create encryptor

        var aes = new RijndaelManaged();

        aes.KeySize = 128;

        aes.BlockSize = 128;

        aes.Padding = PaddingMode.PKCS7;

        aes.Key = Convert.FromBase64String(AES_Key);

        aes.IV = Convert.FromBase64String(AES_IV);

        var encrypt = aes.CreateEncryptor(aes.Key, aes.IV);

        // Encrypt Input

        byte[] xBuff = null;

        using (var ms = new MemoryStream())

        {

            // Convert from UTF-8 String to byte array, write to memory stream and encrypt, then convert to byte array

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

            {

                byte[] xXml = Encoding.UTF8.GetBytes(Input);

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

            }

            xBuff = ms.ToArray();

        }

        // Convert from byte array to base64 string then return

        String Output = Convert.ToBase64String(xBuff);

        return Output;

    }

    /*

     * Decrypt method

     * Both Keys and IVs need to be 16 characters encoded in base64. 

     */ 

    public static String AES_decrypt(String Input, String AES_Key, String AES_IV)

    {

        // Create decryptor

        RijndaelManaged aes = new RijndaelManaged();

        aes.KeySize = 128;

        aes.BlockSize = 128;

        aes.Mode = CipherMode.CBC;

        aes.Padding = PaddingMode.PKCS7;

        aes.Key = Convert.FromBase64String(AES_Key);

        aes.IV = Convert.FromBase64String(AES_IV);

        var decrypt = aes.CreateDecryptor();

        // Decrypt Input

        byte[] xBuff = null;

        using (var ms = new MemoryStream())

        {

            // Convert from base64 string to byte array, write to memory stream and decrypt, then convert to byte array.

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

            {

                byte[] xXml = Convert.FromBase64String(Input);

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

            }

            xBuff = ms.ToArray();

        }

        // Convert from byte array to UTF-8 string then return

        String Output = Encoding.UTF8.GetString(xBuff);

        return Output;

    }

    public static void Main()

    {

        Console.WriteLine("Hello World");

        string message = "My secret message 1234";

​

​

        string iv = "hAC8hMf3N5Zb/DZhFKi6Sg==";

        string key = "AAECAwQFBgcICQoLDA0ODw==";

        string a = AES_encrypt(message, key, iv);

        string b = AES_decrypt(a,key, iv);

​

Console.WriteLine(a);

        Console.WriteLine(b);

​

    }

}