?using System;
using System.Text; 
using System.Net; 
using System.IO; 
using System.Threading;
using System.Text.RegularExpressions;

public class HTMLHelper
{
    #region 私有字段
    private static CookieContainer cc = new CookieContainer();
    private static string contentType = "application/x-www-form-urlencoded";
    private static string accept = "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, application/x-silverlight, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, application/x-ms-application, application/x-ms-xbap, application/vnd.ms-xpsdocument, application/xaml+xml, application/x-silverlight-2-b1, */*";
    private static string userAgent = "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648; .NET CLR 3.5.21022)";
    private static Encoding encoding = Encoding.GetEncoding("utf-8");
    private static int delay = 1000;
    private static int maxTry = 300;
    private static int currentTry = 0;
    #endregion

    #region 公有屬性
    /// <summary> 
    /// Cookie
    /// </summary> 
    public static CookieContainer CookieContainer
    {
        get
        {
            return cc;
        }
    }

    /// <summary> 
    /// 語言
    /// </summary> 
    public static Encoding Encoding
    {
        get
        {
            return encoding;
        }
        set
        {
            encoding = value;
        }
    }

    public static int NetworkDelay
    {
        get
        {
            Random r = new Random();
            return (r.Next(delay, delay * 2));
        }
        set
        {
            delay = value;
        }
    }

    public static int MaxTry
    {
        get
        {
            return maxTry;
        }
        set
        {
            maxTry = value;
        }
    }
    #endregion

    #region 獲取HTML
    /// <summary>
    /// 獲取HTML
    /// </summary>
    /// <param name="url">地址</param>
    /// <param name="postData">post 提交的字符串</param>
    /// <param name="isPost">是否是post</param>
    /// <param name="cookieContainer">CookieContainer</param>
    public static string GetHtml(string url, string postData, bool isPost, CookieContainer cookieContainer)
    {
        if (string.IsNullOrEmpty(postData)) return GetHtml(url, cookieContainer);
        Thread.Sleep(NetworkDelay);
        currentTry++;
        HttpWebRequest httpWebRequest = null;
        HttpWebResponse httpWebResponse = null;
        try
        {
            byte[] byteRequest = Encoding.Default.GetBytes(postData);
            httpWebRequest = (HttpWebRequest)HttpWebRequest.Create(url);
            httpWebRequest.CookieContainer = cookieContainer;
            httpWebRequest.ContentType = contentType;
            httpWebRequest.ServicePoint.ConnectionLimit = maxTry;
            httpWebRequest.Referer = url;
            httpWebRequest.Accept = accept;
            httpWebRequest.UserAgent = userAgent;
            httpWebRequest.Method = isPost ? "POST" : "GET";
            httpWebRequest.ContentLength = byteRequest.Length;
            Stream stream = httpWebRequest.GetRequestStream();
            stream.Write(byteRequest, 0, byteRequest.Length);
            stream.Close();
            httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
            Stream responseStream = httpWebResponse.GetResponseStream();
            StreamReader streamReader = new StreamReader(responseStream, encoding);
            string html = streamReader.ReadToEnd();
            streamReader.Close();
            responseStream.Close();
            currentTry = 0;
            httpWebRequest.Abort();
            httpWebResponse.Close();
            return html;
        }
        catch (Exception e)
        {
            if (currentTry <= maxTry) GetHtml(url, postData, isPost, cookieContainer);
            currentTry--;
            if (httpWebRequest != null)  httpWebRequest.Abort();
            if (httpWebResponse != null) httpWebResponse.Close();
            return string.Empty;
        }
    }

    /// <summary>
    /// 獲取HTML
    /// </summary>
    /// <param name="url">地址</param>
    /// <param name="cookieContainer">CookieContainer</param>
    public static string GetHtml(string url, CookieContainer cookieContainer)
    {
        Thread.Sleep(NetworkDelay);
        currentTry++;
        HttpWebRequest httpWebRequest = null;
        HttpWebResponse httpWebResponse = null;
        try
        {
            httpWebRequest = (HttpWebRequest)HttpWebRequest.Create(url);
            httpWebRequest.CookieContainer = cookieContainer;
            httpWebRequest.ContentType = contentType;
            httpWebRequest.ServicePoint.ConnectionLimit = maxTry;
            httpWebRequest.Referer = url;
            httpWebRequest.Accept = accept;
            httpWebRequest.UserAgent = userAgent;
            httpWebRequest.Method = "GET";
            httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
            Stream responseStream = httpWebResponse.GetResponseStream();
            StreamReader streamReader = new StreamReader(responseStream, encoding);
            string html = streamReader.ReadToEnd();
            streamReader.Close();
            responseStream.Close();
            currentTry--;
            httpWebRequest.Abort();
            httpWebResponse.Close();
            return html;
        }
        catch (Exception e)
        {
            if (currentTry <= maxTry) GetHtml(url, cookieContainer);
            currentTry--;
            if (httpWebRequest != null)  httpWebRequest.Abort();
            if (httpWebResponse != null) httpWebResponse.Close();
            return string.Empty;
        }
    }
    #endregion

    #region 獲取字符流
    /// <summary>
    /// 獲取字符流
    /// </summary>
    //---------------------------------------------------------------------------------------------------------------
    // 示例:
    // System.Net.CookieContainer cookie = new System.Net.CookieContainer(); 
    // Stream s = HttpHelper.GetStream("http://ptlogin2.qq.com/getimage?aid=15000102&0.43878429697395826", cookie);
    // picVerify.Image = Image.FromStream(s);
    //---------------------------------------------------------------------------------------------------------------
    /// <param name="url">地址</param>
    /// <param name="cookieContainer">cookieContainer</param>
    public static Stream GetStream(string url, CookieContainer cookieContainer)
    {
        currentTry++;

        HttpWebRequest httpWebRequest = null;
        HttpWebResponse httpWebResponse = null;

        try
        {
            httpWebRequest = (HttpWebRequest)HttpWebRequest.Create(url);
            httpWebRequest.CookieContainer = cookieContainer;
            httpWebRequest.ContentType = contentType;
            httpWebRequest.ServicePoint.ConnectionLimit = maxTry;
            httpWebRequest.Referer = url;
            httpWebRequest.Accept = accept;
            httpWebRequest.UserAgent = userAgent;
            httpWebRequest.Method = "GET";

            httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
            Stream responseStream = httpWebResponse.GetResponseStream();
            currentTry--;
            return responseStream;
        }
        catch (Exception e)
        {
            if (currentTry <= maxTry)
            {
                GetHtml(url, cookieContainer);
            }

            currentTry--;

            if (httpWebRequest != null)
            {
                httpWebRequest.Abort();
            } if (httpWebResponse != null)
            {
                httpWebResponse.Close();