DES加密/解密

/// <summary>

    /// DES加密/解密类。

    /// </summary>

    public class DESEncrypt

    {



        #region ========加密========



        /// <summary>

        /// 加密

        /// </summary>

        /// <param name="Text"></param>

        /// <returns></returns>

        public static string Encrypt(string Text)

        {

            return Encrypt(Text, "Www.EasaA.Com");

        }

        /// <summary> 

        /// 加密数据 

        /// </summary> 

        /// <param name="Text"></param> 

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

        /// <returns></returns> 

        public static string Encrypt(string Text, string sKey)

        {

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            byte[] inputByteArray;

            inputByteArray = Encoding.Default.GetBytes(Text);

            des.Key = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));

            des.IV = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));

            System.IO.MemoryStream ms = new System.IO.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);

            }

            return ret.ToString();

        }



        #endregion



        #region ========解密========





        /// <summary>

        /// 解密

        /// </summary>

        /// <param name="Text"></param>

        /// <returns></returns>

        public static string Decrypt(string Text)

        {

            return Decrypt(Text, "Www.EasaA.Com");

        }

        /// <summary> 

        /// 解密数据 

        /// </summary> 

        /// <param name="Text"></param> 

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

        /// <returns></returns> 

        public static string Decrypt(string Text, string sKey)

        {

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            int len;

            len = Text.Length / 2;

            byte[] inputByteArray = new byte[len];

            int x, i;

            for (x = 0; x < len; x++)

            {

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

                inputByteArray[x] = (byte)i;

            }

            des.Key = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));

            des.IV = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));

            System.IO.MemoryStream ms = new System.IO.MemoryStream();

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

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

            cs.FlushFinalBlock();

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

        }



        #endregion



    }