/// <summary>
        /// MD5轉碼
        /// </summary>
        /// <param name="str">未加密的文字</param>
        /// <returns></returns>
        public static string Str_MD5(string str)
        {
            byte[] textByte = MD5.Create().ComputeHash(Encoding.Default.GetBytes(str));
            
 
return BitConverter.ToString(textByte).Replace("-", "");
        }


        /// <summary>
        /// Unicode轉碼
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public static string Str_Unicode(string str)
        {
            StringBuilder sb 
 
= new StringBuilder();
            byte[] byStr = System.Text.Encoding.UTF8.GetBytes(str); //預設是System.Text.Encoding.Default.GetBytes(str)
            for (int i = 0; i < byStr.Length; i++)
            {
                sb.Append(@"%" + Convert.ToString(byStr[i], 16));
            }
            return
 
 (sb.ToString());
        }


        /// <summary>
        /// 獲取當前時間戳（秒）（string型別）
        /// </summary>
        /// <returns></returns>
        public static string GetNowTime_Sec()
        {
            TimeSpan ts = DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, 0);
            return Convert.ToInt64(ts.TotalSeconds).ToString();
        }


        /// <summary>
        /// SHA1加密
        /// </summary>
        /// <param name="value"></param>
        /// <returns></returns>
        public static string SHA1Hash(string value)
        {
            SHA1 sha1 = new SHA1CryptoServiceProvider();
            byte[] bytes_sha1_in = UTF8Encoding.Default.GetBytes(value);
            byte[] bytes_sha1_out = sha1.ComputeHash(bytes_sha1_in);
            string str_shal_out = BitConverter.ToString(bytes_sha1_out);
            str_shal_out = str_shal_out.Replace("-", "");
            return str_shal_out;
        }