C# 加密字符串（RijndaelManaged）

public static string GetNewToken(string loginName, string randomKey, string culture, string country)
            {
                byte[] plainBytes = Encoding.UTF8.GetBytes(
                    CreatePlainText(loginName, randomKey, culture, country)
                    );
                RijndaelManaged aes = new RijndaelManaged();
                aes.KeySize = 256;
                aes.Key = Aes256Key;
                aes.Mode = CipherMode.ECB;
                RijndaelManagedTransform encryptor = aes.CreateEncryptor() as RijndaelManagedTransform;
                byte[] result = encryptor.TransformFinalBlock(plainBytes, 0, plainBytes.Length);

                return Helper.ToString64(result);
            }