mORMot Open Source

public static string encrypt(string value, string key)

        {

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            des.Mode = CipherMode.CBC;

            des.Padding = PaddingMode.PKCS7;

            des.Key = ASCIIEncoding.ASCII.GetBytes(key);

            des.IV = ASCIIEncoding.ASCII.GetBytes(key);



            ICryptoTransform encryptor = des.CreateEncryptor();

            byte[] messageBytes = System.Text.ASCIIEncoding.ASCII.GetBytes(value);

            byte[] encryptedBytes = encryptor.TransformFinalBlock(messageBytes, 0, messageBytes.Length);



            return Convert.ToBase64String(encryptedBytes);

        }