ASP.NET 2.0 加密 Cookies

//加密 Cookies
//Response.Cookies["askCRM"]["USERID"] = Tools.Encrypt(strUserName.Trim(), Tools.myKey);
//解密
//string strUid = Request.Cookies["askCRM"]["USERID"];
//strUid = Tools.Decrypt(strUid, Tools.myKey);

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

/// <summary>
/// Tools 的摘要说明

/// </summary>
///
namespace HuiTong.Common
{
    public class Tools
    {

        /// <summary>
        /// 当前程序加密所使用的密钥

        /// </summary>
        public static readonly string sKey = "w0x3hd89";

        #region 加密方法
        /// <summary>
        /// 加密方法
        /// </summary>
        /// <param name="pToEncrypt">需要加密字符串</param>
        /// <param name="sKey">密钥</param>
        /// <returns>加密后的字符串</returns>
        public static string Encrypt(string pToEncrypt)
        {
            try
            {
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                //把字符串放到byte数组中

                //原来使用的UTF8编码，我改成Unicode编码了，不行
                byte[] inputByteArray = Encoding.Default.GetBytes(pToEncrypt);

                //建立加密对象的密钥和偏移量

                //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();
            }
            catch (Exception ex)
            {
     
            }

            return "";
        }
        #endregion

        #region 解密方法
        /// <summary>
        /// 解密方法
        /// </summary>
        /// <param name="pToDecrypt">需要解密的字符串</param>
        /// <param name="sKey">密匙</param>
        /// <returns>解密后的字符串</returns>
        public static string Decrypt(string pToDecrypt)
        {
            try
            {
                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;
                }

                //建立加密对象的密钥和偏移量，此值重要，不能修改
                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();
                //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)
            {
 
            }
            return "";
        }
        #endregion
    }
}