using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Security.Cryptography;

using System.IO;



namespace PwcTool

{

    public class MyDes

    {

        /// <summary>

        /// DES加密方法

        /// </summary>

        /// <param name="strPlain">明文</param>

        /// <param name="strDESKey">密钥</param>

        /// <param name="strDESIV">向量</param>

        /// <returns>密文</returns>

        public static string Encode(string source, string _DESKey)

        {

            StringBuilder sb = new StringBuilder();

            using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())

            {

                byte[] key = ASCIIEncoding.ASCII.GetBytes(_DESKey);

                byte[] iv = ASCIIEncoding.ASCII.GetBytes(_DESKey);

                byte[] dataByteArray = Encoding.UTF8.GetBytes(source);

                des.Mode = System.Security.Cryptography.CipherMode.CBC;

                des.Key = key;

                des.IV = iv;

                string encrypt = "";

                using (MemoryStream ms = new MemoryStream())

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

                {

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

                    cs.FlushFinalBlock();

                    encrypt = Convert.ToBase64String(ms.ToArray());

                }

                return encrypt;

            }

        }



        /// <summary>

        /// 进行DES解密。

        /// </summary>

        /// <param name="pToDecrypt">要解密的base64串</param>

        /// <param name="sKey">密钥，且必须为8位。</param>

        /// <returns>已解密的字符串。</returns>

        public static string Decode(string source, string sKey)

        {

            byte[] inputByteArray = System.Convert.FromBase64String(source);//Encoding.UTF8.GetBytes(source);

            using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())

            {

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

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

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

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

                {

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

                    cs.FlushFinalBlock();

                    cs.Close();

                }

                string str = Encoding.UTF8.GetString(ms.ToArray());

                ms.Close();

                return str;

            }

        }

    }

}