DES加密算法

 

using System;
using System.Data;
using System.Configuration;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.IO;
using System.Text;
using System.Security.Cryptography;

/// <summary>
///HEYCcrypt 的摘要说明
/// </summary>
public class HEYCcrypt
{
    public HEYCcrypt()
    {
        //
        //TODO: 在此处添加构造函数逻辑
        //
    }
    public static string skey = "asdfghjk";
    /// <summary>
    /// 对称加密解密的密匙
    /// </summary>
    public string Skey
    {
        get { return skey; }
        set { skey = value; }
    }
    /// <summary>
    /// 加密
    /// </summary>
    /// <param name="pToEncrypt"></param>
    /// <returns></returns>
    public static string Encrypt(string pToEncrypt)
    {
        try
        {
            //访问数据加密标准(DES)算法的加密服务提供程序 (CSP) 版本的包装对象
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();
            des.Key = ASCIIEncoding.ASCII.GetBytes(skey);//建立加密对象的密钥和偏移量
            des.IV = ASCIIEncoding.ASCII.GetBytes(skey); //原文使用ASCIIEncoding.ASCII方法的GetBytes方法
            byte[] inputbyteArray = Encoding.Default.GetBytes(pToEncrypt);//把字符串放到byte数组中
            MemoryStream ms = new MemoryStream();//创建其支持存储区为内存的流　
            //定义将数据流链接到加密转换的流
            CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);
            cs.Write(inputbyteArray, 0, inputbyteArray.Length);
            cs.FlushFinalBlock();
            //上面已经完成了把加密后的结果放到内存中去
            StringBuilder ret = new StringBuilder();
            foreach (byte b in ms.ToArray())
            {
                ret.AppendFormat("{0:X2}", b);
            }
            return ret.ToString();
        }
        catch (Exception ex)
        {
            throw (ex);
        }
    }
    /// <summary>
    /// 解密
    /// </summary>
    /// <param name="pToDecrypt"></param>
    /// <returns></returns>
    public static string Decrypt(string pToDecrypt)
    {
        try
        {
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();
            byte[] inputbyteArray = new byte[pToDecrypt.Length / 2];
            for (int i = 0; i < pToDecrypt.Length / 2; i++)
            {
                int x = Convert.ToInt32(pToDecrypt.Substring(i * 2, 2), 16);
                inputbyteArray[i] = (byte)x;
            }
            des.Key = ASCIIEncoding.ASCII.GetBytes(skey);//建立加密对象的密钥和偏移量，此值重要，不能修改
            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();
            //建立StringBuild对象，createDecrypt使用的是流对象，必须把解密后的文本变成流对象
            StringBuilder ret = new StringBuilder();
            return System.Text.Encoding.Default.GetString(ms.ToArray());
        }
        catch (Exception ex)
        {
            throw (ex);
        }
    }
}