C# SHA512和Base64加解密方法

        /// <summary>
        /// Get SHA512 Hash From String
        /// </summary>
        /// <param name="originalData"></param>
        /// <returns></returns>
        static public string GetHash512String(string originalData)
        {
            string result = string.Empty;
            byte[] bytValue = Encoding.UTF8.GetBytes(originalData);
            SHA512 sha512 = new SHA512CryptoServiceProvider();
            byte[] retVal = sha512.ComputeHash(bytValue);
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < retVal.Length; i++)
            {
                sb.Append(retVal[i].ToString("x2"));
            }
            result = sb.ToString();
            return result;
        }

        /// <summary>
        /// Dictionary Parse To String
        /// </summary>
        /// <param name="parameters">Dictionary</param>
        /// <returns>String</returns>
        static public string ParseToString(IDictionary<string, string> parameters)
        {
            IDictionary<string, string> sortedParams = new SortedDictionary<string, string>(parameters);
            IEnumerator<KeyValuePair<string, string>> dem = sortedParams.GetEnumerator();

            StringBuilder query = new StringBuilder("");
            while (dem.MoveNext())
            {
                string key = dem.Current.Key;
                string value = dem.Current.Value;
                if (!string.IsNullOrEmpty(key) && !string.IsNullOrEmpty(value))
                {
                    query.Append(key).Append("=").Append(value).Append("&");
                }
            }
            string content = query.ToString().Substring(0, query.Length - 1);

            return content;
        }

        /// <summary>
        /// String Parse To Dictionary
        /// </summary>
        /// <param name="parameter">String</param>
        /// <returns>Dictionary</returns>
        static public Dictionary<string, string> ParseToDictionary(string parameter)
        {
            String[] dataArry = parameter.Split('&');
            Dictionary<string, string> dataDic = new Dictionary<string, string>();
            for (int i = 0; i <= dataArry.Length - 1; i++)
            {
                String dataParm = dataArry[i];
                int dIndex = dataParm.IndexOf("=");
                if (dIndex != -1)
                {
                    String key = dataParm.Substring(0, dIndex);
                    String value = dataParm.Substring(dIndex + 1, dataParm.Length - dIndex - 1);
                    dataDic.Add(key, value);
                }
            }

            return dataDic;
        }
        
        static public string Base64Encode(string data)
        {
            string result = data;

            byte[] encData_byte = Encoding.UTF8.GetBytes(data);
            result = Convert.ToBase64String(encData_byte);

            return result;
        }
        
        static public string Base64Decode(string data)
        {
            string result = data;
            string decode = string.Empty;

            UTF8Encoding encoder = new UTF8Encoding();
            Decoder utf8Decode = encoder.GetDecoder();
            byte[] todecode_byte = Convert.FromBase64String(data);
            int charCount = utf8Decode.GetCharCount(todecode_byte, 0, todecode_byte.Length);
            char[] decoded_char = new char[charCount];
            utf8Decode.GetChars(todecode_byte, 0, todecode_byte.Length, decoded_char, 0);
            result = new String(decoded_char);

            return result;
        }