using System;
using System.Text;
using System.IO;
using System.Security.Cryptography;

namespace HRManager.CommonComponent
{
    /// <summary>
    /// 字符串加密、解密類，利用DES算法
    /// </summary>
    public class myEncrypt
    {
        private static byte[] key = new byte[] { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
        private static byte[] iv = new byte[] { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };

        /// <summary>
        /// 加密
        /// </summary>
        /// <param name="notEncryptStr">待加密的明文字符串</param>
        /// <returns>加密后的字符串</returns>
        public static string EncryptString(string notEncryptStr)
        {
            //初始化加密器生成器
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            byte[] byteNotEncrypt = Encoding.UTF8.GetBytes(notEncryptStr);//將字符串轉(zhuǎn)換成字節(jié)
            MemoryStream encryptMs = new MemoryStream();//創(chuàng)建內(nèi)存數(shù)據(jù)流
            CryptoStream encryptCs = new CryptoStream(encryptMs, des.CreateEncryptor(key,iv), CryptoStreamMode.Write);//創(chuàng)建加密器

            //加密數(shù)據(jù)
            encryptCs.Write(byteNotEncrypt, 0, byteNotEncrypt.Length);//將字節(jié)加密并寫入內(nèi)存
            encryptCs.FlushFinalBlock();//將緩存中的數(shù)據(jù)寫入內(nèi)存
            encryptMs.Seek(0, SeekOrigin.Begin);//回到內(nèi)存流開始的位置

            //將加密后的數(shù)據(jù)讀取出來
            byte[] byteEncrypt = new byte[1024];
            int i = encryptMs.Read(byteEncrypt, 0, 1024);

            encryptCs.Close();

            //將加密后的字節(jié)轉(zhuǎn)換為BASE64編碼
            string decryptStr = Convert.ToBase64String(byteEncrypt, 0, i);
            return decryptStr;
        }

        void test()
        {
            string str1 = "Hello";
            string str2 = myEncrypt.EncryptString(str1);
        }

        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="decryptStr">待解密的密文字符串</param>
        /// <returns>解密后的字符串</returns>
        public static string DecryptString(string decryptStr)
        {
            //初始化解密器生成器
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();


            byte[] byteNotDecrypt = Convert.FromBase64String(decryptStr);//將加密后的BASE64編碼的字符串轉(zhuǎn)換成字節(jié)
            MemoryStream decryptMs = new MemoryStream(byteNotDecrypt);//創(chuàng)建內(nèi)存數(shù)據(jù)流
            CryptoStream decryptCs = new CryptoStream(decryptMs, des.CreateDecryptor(key, iv), CryptoStreamMode.Read);//創(chuàng)建解密器

            //解密數(shù)據(jù)
            byte[] byteDecrypt = new byte[1024];
            int i = decryptCs.Read(byteDecrypt, 0, 1024);
            decryptCs.Close();

            //將解密后的字節(jié)轉(zhuǎn)換為BASE64編碼
            string notEncryptStr = Encoding.UTF8.GetString(byteDecrypt, 0, i);
            return notEncryptStr;
        }
    }
}