DES復号化実現方式

private static readonly byte[] _keys = { 0x22, 0x84, 0x56, 0x98, 0x90, 0xAB, 0xpD, 0xEF };

        private static readonly byte[] _ivs = { 0xAB, 0xCD, 0xEF, 0x12, 0x34, 0x56, 0x78, 0x90 };

        /// <summary>

        ///  

        /// </summary>

        /// <param name="pToEncrypt"> </param>

        /// <returns></returns>

        public string Encrypt(string pToEncrypt)

        {

            var des = new DESCryptoServiceProvider();

            try

            {

                var inputByteArray = Encoding.UTF8.GetBytes(pToEncrypt);

                des.Key = _keys;

                des.IV = _ivs;

                var ms = new MemoryStream();

                var cs = new CryptoStream(ms, des.CreateEncryptor(),

                CryptoStreamMode.Write);

                cs.Write(inputByteArray, 0, inputByteArray.Length);

                cs.FlushFinalBlock();

                var ret = new StringBuilder();

                foreach (byte b in ms.ToArray())

                {

                    ret.AppendFormat("{0:X2}", b);

                }



                return ret.ToString();

            }

            catch

            {

                return pToEncrypt;

            }

            finally

            {

                des = null;

            }

        }



        /// <summary>

        ///  

        /// </summary>

        /// <param name="pToDecrypt"> </param>

        /// <returns></returns>

        public string Decrypt(string pToDecrypt)

        {

            var des = new DESCryptoServiceProvider();

            try

            {

                var inputByteArray = new byte[pToDecrypt.Length / 2];

                for (var x = 0; x < pToDecrypt.Length / 2; x++)

                {

                    var i = (Convert.ToInt32(pToDecrypt.Substring(x * 2, 2), 16));

                    inputByteArray[x] = (byte)i;

                }



                // 

                des.Key = _keys;

                des.IV = _ivs;

                var ms = new MemoryStream();

                var cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);

                cs.Write(inputByteArray, 0, inputByteArray.Length);

                cs.FlushFinalBlock();

                return Encoding.UTF8.GetString(ms.ToArray());

            }

            catch

            {

                return pToDecrypt;

            }

            finally

            {

                des = null;

            }

        }