一个完整版的HttpHelper.cs类型

using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.IO;
using System.Text.RegularExpressions;
using System.IO.Compression;
using System.Security.Cryptography.X509Certificates;
using System.Net.Security;

namespace QQMsgBatchSendPrj
{
    /// <summary>  
    /// Http连接操作帮助类  
    /// </summary>  
    public class HttpHelper
    {
        #region 预定义方变量
        //默认的编码  
        private Encoding encoding = Encoding.Default;
        //Post数据编码  
        private Encoding postencoding = Encoding.Default;
        //HttpWebRequest对象用来发起请求  
        private HttpWebRequest request = null;
        //获取影响流的数据对象  
        private HttpWebResponse response = null;
        //设置本地的出口ip和端口  
        private IPEndPoint _IPEndPoint = null;
        #endregion

        #region Public

        public static HttpHelper Instance = new HttpHelper();

        /// <summary>  
        /// 根据相传入的数据，得到相应页面数据  
        /// </summary>  
        /// <param name="item">参数类对象</param>  
        /// <returns>返回HttpResult类型</returns>  
        public  HttpResult GetHtml(string url, string postString, CookieCollection CookieContainer)
        {
            HttpItem item = new HttpItem()
            {
                URL = url,
                Postdata = postString,
                CookieCollection = CookieContainer
            };

            return GetHtml(item);
        }

        /// <summary>  
        /// 根据相传入的数据，得到相应页面数据  
        /// </summary>  
        /// <param name="item">参数类对象</param>  
        /// <returns>返回HttpResult类型</returns>  
        public  HttpResult GetHtml(string url,CookieCollection CookieContainer)
        {
            HttpItem item = new HttpItem()
            {