private const string KEY = "Gold926!";
        private readonly byte[] _vector = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };

        public string Encode(string encryptString)
        {
            try
            {
                var rgbKey = Encoding.UTF8.GetBytes(KEY.Substring(0, 8));
                var des = new DESCryptoServiceProvider();

                var inputByteArray = Encoding.UTF8.GetBytes(encryptString);
                var ms = new MemoryStream();
                var cs = new CryptoStream(ms, des.CreateEncryptor(rgbKey, _vector), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();

                return Convert.ToBase64String(ms.ToArray());
            }
            catch (Exception)
            {
                return null;
            }
        }

        public string Decode(string decryptString)
        {
            try
            {
                var provider = new DESCryptoServiceProvider();
                var rgbKey = Encoding.UTF8.GetBytes(KEY.Substring(0, 8));

                var inputByteArray = Convert.FromBase64String(decryptString);

                var ms = new MemoryStream();
                var cs = new CryptoStream(ms, provider.CreateDecryptor(rgbKey, _vector), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();

                var encoding = new UTF8Encoding();

                return encoding.GetString(ms.ToArray());
            }
            catch (Exception)
            {
                return null;
            }
        }