DESCryptoServiceProvider 加密与解密

using System.Security.Cryptography;

        /// <summary>

        /// 加密

        /// </summary>

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

        /// <param name="sKey"></param>

        /// <returns></returns>

        public string Encrypt(string pToEncrypt, string sKey)

        {

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            byte[] inputByteArray = Encoding.GetEncoding("UTF-8").GetBytes(pToEncrypt);

            //建立加密对象的密钥和偏移量

            //原文使用ASCIIEncoding.ASCII方法的GetBytes方法

            //使得输入密码必须输入英文文本

            des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);

            des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);

            MemoryStream ms = new MemoryStream();

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

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

            cs.FlushFinalBlock();

            StringBuilder ret = new StringBuilder();

            foreach (byte b in ms.ToArray())

            {

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

            }

            ret.ToString();

            return ret.ToString();

        }

        /// <summary>

        /// 解密

        /// </summary>

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

        /// <param name="sKey"></param>

        /// <returns></returns>

        public string Decrypt(string pToDecrypt, string sKey)

        {

                DESCryptoServiceProvider des = new DESCryptoServiceProvider();

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

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

                {

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

                    inputByteArray[x] = (byte)i;

                }

                des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);

                des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);

                MemoryStream ms = new MemoryStream();

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

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

                cs.FlushFinalBlock();

                StringBuilder ret = new StringBuilder();

                return System.Text.Encoding.Default.GetString(ms.ToArray());

        }