C # learning how to use AES and aesmanaged

Encryption

static byte[] EncryptBytes_Aes(byte[] plainText, byte[] Key, byte[] IV)        {            // Check arguments.            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("IV");            byte[] encrypted;            // Create an AesManaged object            // with the specified key and IV.            using (AesManaged aesAlg = new AesManaged())            {                aesAlg.Key = Key;                aesAlg.IV = IV;                // 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 (BinaryWriter bw = new BinaryWriter(csEncrypt))                        {                            bw.Write(plainText);                        }                    }                    encrypted = msEncrypt.ToArray();                }            }            // Return the encrypted bytes from the memory stream.            return encrypted;        }

Decryption

static byte[] DecryptBytes_Aes(byte[] cipherText, byte[] Key, byte[] IV)        {            // Check arguments.            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("IV");            // Declare the string used to hold            // the decrypted text.            List<byte> plaintext = new List<byte>();            // Create an AesManaged object            // with the specified key and IV.            using (AesManaged aesAlg = new AesManaged())            {                aesAlg.Key = Key;                aesAlg.IV = IV;                // Create a decrytor to perform the stream transform.                ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);                // Create the streams used for decryption.                using (MemoryStream msDecrypt = new MemoryStream(cipherText))                {                    using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))                    {                        using (BinaryReader br = new BinaryReader(csDecrypt))                        {                            int bufferLen = 1024;                            byte[] buffer = new byte[bufferLen];                            int read = 0;                            while ((read = br.Read(buffer, 0, bufferLen)) > 0)                                plaintext.AddRange(buffer.Take(read));                        }                    }                }            }            return plaintext.ToArray();        }

Demo:

String STR = "test ase, let's test AES"; byte [] plainbytes = encoding. utf8.getbytes (STR); Using (aesmanaged AES = new aesmanaged () {byte [] ebytes = encryptbytes_aes (plainbytes, AES. key, AES. IV); byte [] dbytes = decryptbytes_aes (ebytes, AES. key, AES. IV); // outputbytes (plainbytes); // outputbytes (ebytes); // outputbytes (dbytes); console. writeline ("plaintext: {0}", STR); console. writeline ("plaintext array: {0}", formatbytes (plainbytes); console. writeline ("encrypted array: {0}", formatbytes (ebytes); console. writeline ("decrypted array: {0}", formatbytes (dbytes); console. writeline ("decrypted plaintext: {0}", encoding. utf8.getstring (dbytes ));}

static string FormatBytes(byte[] bytes,byte countInLine = 10)        {            StringBuilder sb = new StringBuilder();            int i = 0;            foreach (byte b in bytes)            {                if (i++ % countInLine == 0)                    sb.Append(‘\n‘);                sb.Append(String.Format("{0:X2}  ", b));            }            sb.Append(‘\b‘);            return sb.ToString();        }