Example of Advanced Encryption Standard (AES) in c#.net

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

using System.Security.Cryptography;

using System.IO;

namespace WindowsFormsApplication2

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private void Form1_Load(object sender, EventArgs e)

        {

            try

            {

                string original = "jay jagannath";

                using (Aes myAes = Aes.Create())

                {

                    byte[] encrypted = EncryptStringToBytes_Aes(original, myAes.Key, myAes.IV);

                    string roundtrip = DecryptStringFromBytes_Aes(encrypted, myAes.Key, myAes.IV);

                    MessageBox.Show(roundtrip.ToString());

                }

            }

            catch (Exception ex)

            {

                MessageBox.Show(ex.ToString());

            }

        }

        static string DecryptStringFromBytes_Aes(byte[] cipherText, byte[] Key, byte[] IV)

        {

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

                throw new ArgumentNullException("cipherText");

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

                throw new ArgumentNullException("Key");

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

                throw new ArgumentNullException("Key");

            string plaintext = null;

            using (Aes aesAlg = Aes.Create())

            {

                aesAlg.Key = Key;

                aesAlg.IV = IV;

                ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);

                using (MemoryStream msDecrypt = new MemoryStream(cipherText))

                {

                    using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))

                    {

                        using (StreamReader srDecrypt = new StreamReader(csDecrypt))

                        {

                            plaintext = srDecrypt.ReadToEnd();

                        }

                    }

                }

            }

            return plaintext;

        }

        static byte[] EncryptStringToBytes_Aes(string plainText, byte[] Key, byte[] IV)

        {

            if (plainText == null || plainText.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("Key");

            byte[] encrypted;

            using (Aes aesAlg = Aes.Create())

            {

                aesAlg.Key = Key;

                aesAlg.IV = IV;

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

                using (MemoryStream msEncrypt = new MemoryStream())

                {

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

                    {

                        using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))

                        {

                            swEncrypt.Write(plainText);

                        }

                        encrypted = msEncrypt.ToArray();

                    }

                }

            }

            return encrypted;

        }

    }

}