RijndaelManaged 加解密

/// <summary>
        /// 加密
        /// </summary>
        /// <param name="jsonStr"></param>
        /// <returns></returns>
        private static string Pass(string jsonStr)
        {
            byte[] keyArray = UTF8Encoding.UTF8.GetBytes(key);
            RijndaelManaged rm = new RijndaelManaged();
            rm.Key = keyArray;
            rm.Mode = CipherMode.ECB;
            rm.Padding = PaddingMode.PKCS7;
            ICryptoTransform cTransform = rm.CreateEncryptor();
            byte[] bytes = UTF8Encoding.UTF8.GetBytes(jsonStr);
            byte[] encryptArray = cTransform.TransformFinalBlock(bytes, 0, bytes.Length);
            jsonStr = Convert.ToBase64String(encryptArray, 0, encryptArray.Length);
            return jsonStr;
        }
        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="_str"></param>
        /// <returns></returns>
        private static string Decrypt(string _str)
        {
            byte[] keyArray = UTF8Encoding.UTF8.GetBytes(key);
            RijndaelManaged rm = new RijndaelManaged();
            rm.Key = keyArray;
            rm.Mode = CipherMode.ECB;
            rm.Padding = PaddingMode.PKCS7;
            ICryptoTransform cTransform = rm.CreateDecryptor();
            byte[] bytes = Convert.FromBase64String(_str);
            byte[] encryptArray = cTransform.TransformFinalBlock(bytes, 0, bytes.Length);
            _str = UTF8Encoding.UTF8.GetString(encryptArray, 0, encryptArray.Length);
            return _str;
        }