- using System;
- using System.Data;
- using System.Configuration;
- using System.Net;
- using System.IO;
- using System.Text;
- using System.Collections.Generic;
- using System.Text.RegularExpressions;
- using System.Threading;
- using System.Web;
- namespace MyWebPage
- {
- public class Link
- {
- public string Text
- {
- get;
- set;
- }
- public string NavigateUrl
- {
- get;
- set;
- }
- }
- /// <summary>
- /// 网页类
- /// </summary>
- public class WebPage
- {
- #region 私有成员
- private Uri m_uri; //url
- private List<Link> m_links=new List<Link>(); //此网页上的链接
- private string m_title=""; //标题
- private string m_html=""; //HTML代码
- private string m_outstr=""; //网页可输出的纯文本
- private bool m_good; //网页是否可用
- private int m_pagesize; //网页的大小
- private static Dictionary<string, CookieContainer> webcookies = new Dictionary<string, CookieContainer>();//存放所有网页的Cookie
- #endregion
- #region 属性
- /// <summary>
- /// 通过此属性可获得本网页的网址,只读
- /// </summary>
- public string URL
- {
- get
- {
- return m_uri.AbsoluteUri;
- }
- }
- /// <summary>
- /// 通过此属性可获得本网页的标题,只读
- /// </summary>
- public string Title
- {
- get
- {
- if (m_title == "")
- {
- Regex reg = new Regex(@"(?m)<title[^>]*>(?<title>(?:\w|\W)*?)</title[^>]*>", RegexOptions.Multiline | RegexOptions.IgnoreCase);
- Match mc = reg.Match(m_html);
- if (mc.Success)
- m_title = mc.Groups["title"].Value.Trim();
- }
- return m_title;
- }
- }
- public string M_html
- {
- get
- {
- if (m_html == null)
- {
- m_html = "";
- }
- return m_html;
- }
- }
- /// <summary>
- /// 此属性获得本网页的所有链接信息,只读
- /// </summary>
- public List<Link> Links
- {
- get
- {
- if (m_links.Count == 0) getLinks();
- return m_links;
- }
- }
- /// <summary>
- /// 此属性返回本网页的全部纯文本信息,只读
- /// </summary>
- public string Context
- {
- get
- {
- if (m_outstr == "") getContext(Int16.MaxValue);
- return m_outstr;
- }
- }
- /// <summary>
- /// 此属性获得本网页的大小
- /// </summary>
- public int PageSize
- {
- get
- {
- return m_pagesize;
- }
- }
- /// <summary>
- /// 此属性获得本网页的所有站内链接
- /// </summary>
- public List<Link> InsiteLinks
- {
- get
- {
- return getSpecialLinksByUrl("^http://" + m_uri.Host, Int16.MaxValue);
- }
- }
- /// <summary>
- /// 此属性表示本网页是否可用
- /// </summary>
- public bool IsGood
- {
- get
- {
- return m_good;
- }
- }
- /// <summary>
- /// 此属性表示网页的所在的网站
- /// </summary>
- public string Host
- {
- get
- {
- return m_uri.Host;
- }
- }
- #endregion
- /// <summary>
- /// 从HTML代码中分析出链接信息
- /// </summary>
- /// <returns>List<Link></returns>
- private List<Link> getLinks()
- {
- if (m_links.Count == 0)
- {
- Regex[] regex = new Regex[2];
- regex[0] = new Regex(@"<a\shref\s*=""(?<URL>[^""]*).*?>(?<title>[^<]*)</a>", RegexOptions.IgnoreCase | RegexOptions.Singleline);
- regex[1] = new Regex("<[i]*frame[^><]+src=(\"|‘)?(?<url>([^>\"‘\\s)])+)(\"|‘)?[^>]*>", RegexOptions.IgnoreCase);
- for (int i = 0; i < 2; i++)
- {
- Match match = regex[i].Match(m_html);
- while (match.Success)
- {
- try
- {
- string url = HttpUtility.UrlDecode(new Uri(m_uri, match.Groups["URL"].Value).AbsoluteUri);
- string text = "";
- if (i == 0) text = new Regex("(<[^>]+>)|(\\s)|(?)|&|\"", RegexOptions.Multiline | RegexOptions.IgnoreCase).Replace(match.Groups["text"].Value, "");
- Link link = new Link();
- link.Text = text;
- link.NavigateUrl = url;
- m_links.Add(link);
- }
- catch (Exception ex) { Console.WriteLine(ex.Message); };
- match = match.NextMatch();
- }
- }
- }
- return m_links;
- }
- /// <summary>
- /// 此私有方法从一段HTML文本中提取出一定字数的纯文本
- /// </summary>
- /// <param name="instr">HTML代码</param>
- /// <param name="firstN">提取从头数多少个字</param>
- /// <param name="withLink">是否要链接里面的字</param>
- /// <returns>纯文本</returns>
- private string getFirstNchar(string instr, int firstN, bool withLink)
- {
- if (m_outstr == "")
- {
- m_outstr = instr.Clone() as string;
- m_outstr = new Regex(@"(?m)<script[^>]*>(\w|\W)*?</script[^>]*>", RegexOptions.Multiline | RegexOptions.IgnoreCase).Replace(m_outstr, "");
- m_outstr = new Regex(@"(?m)<style[^>]*>(\w|\W)*?</style[^>]*>", RegexOptions.Multiline | RegexOptions.IgnoreCase).Replace(m_outstr, "");
- m_outstr = new Regex(@"(?m)<select[^>]*>(\w|\W)*?</select[^>]*>", RegexOptions.Multiline | RegexOptions.IgnoreCase).Replace(m_outstr, "");
- if (!withLink) m_outstr = new Regex(@"(?m)<a[^>]*>(\w|\W)*?</a[^>]*>", RegexOptions.Multiline | RegexOptions.IgnoreCase).Replace(m_outstr, "");
- Regex objReg = new System.Text.RegularExpressions.Regex("(<[^>]+?>)|?", RegexOptions.Multiline | RegexOptions.IgnoreCase);
- m_outstr = objReg.Replace(m_outstr, "");
- Regex objReg2 = new System.Text.RegularExpressions.Regex("(\\s)+", RegexOptions.Multiline | RegexOptions.IgnoreCase);
- m_outstr = objReg2.Replace(m_outstr, " ");
- }
- return m_outstr.Length > firstN ? m_outstr.Substring(0, firstN) : m_outstr;
- }
- #region 公有文法
- /// <summary>
- /// 此公有方法提取网页中一定字数的纯文本,包括链接文字
- /// </summary>
- /// <param name="firstN">字数</param>
- /// <returns></returns>
- public string getContext(int firstN)
- {
- return getFirstNchar(m_html, firstN, true);
- }
- /// <summary>
- /// 此公有方法从本网页的链接中提取一定数量的链接,该链接的URL满足某正则式
- /// </summary>
- /// <param name="pattern">正则式</param>
- /// <param name="count">返回的链接的个数</param>
- /// <returns>List<Link></returns>
- public List<Link> getSpecialLinksByUrl(string pattern, int count)
- {
- if (m_links.Count == 0) getLinks();
- List<Link> SpecialLinks = new List<Link>();
- List<Link>.Enumerator i;
- i = m_links.GetEnumerator();
- int cnt = 0;
- while (i.MoveNext() && cnt < count)
- {
- if (new Regex(pattern, RegexOptions.Multiline | RegexOptions.IgnoreCase).Match(i.Current.NavigateUrl).Success)
- {
- SpecialLinks.Add(i.Current);
- cnt++;
- }
- }
- return SpecialLinks;
- }
- /// <summary>
- /// 此公有方法从本网页的链接中提取一定数量的链接,该链接的文字满足某正则式
- /// </summary>
- /// <param name="pattern">正则式</param>
- /// <param name="count">返回的链接的个数</param>
- /// <returns>List<Link></returns>
- public List<Link> getSpecialLinksByText(string pattern, int count)
- {
- if (m_links.Count == 0) getLinks();
- List<Link> SpecialLinks = new List<Link>();
- List<Link>.Enumerator i;
- i = m_links.GetEnumerator();
- int cnt = 0;
- while (i.MoveNext() && cnt < count)
- {
- if (new Regex(pattern, RegexOptions.Multiline | RegexOptions.IgnoreCase).Match(i.Current.Text).Success)
- {
- SpecialLinks.Add(i.Current);
- cnt++;
- }
- }
- return SpecialLinks;
- }
- /// <summary>
- /// 这公有方法提取本网页的纯文本中满足某正则式的文字
- /// </summary>
- /// <param name="pattern">正则式</param>
- /// <returns>返回文字</returns>
- public string getSpecialWords(string pattern)
- {
- if (m_outstr == "") getContext(Int16.MaxValue);
- Regex regex = new Regex(pattern, RegexOptions.Multiline | RegexOptions.IgnoreCase);
- Match mc = regex.Match(m_outstr);
- if (mc.Success)
- return mc.Groups[1].Value;
- return string.Empty;
- }
- #endregion
- #region 构造函数
- private void Init(string _url)
- {
- try
- {
- m_uri = new Uri(_url);
- m_links = new List<Link>();
- m_html = "";
- m_outstr = "";
- m_title = "";
- m_good = true;
- if (_url.EndsWith(".rar") || _url.EndsWith(".dat") || _url.EndsWith(".msi"))
- {
- m_good = false;
- return;
- }
- HttpWebRequest rqst = (HttpWebRequest)WebRequest.Create(m_uri);
- rqst.AllowAutoRedirect = true;
- rqst.MaximumAutomaticRedirections = 3;
- rqst.UserAgent = "Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)";
- rqst.KeepAlive = true;
- rqst.Timeout = 10000;
- lock (WebPage.webcookies)
- {
- if (WebPage.webcookies.ContainsKey(m_uri.Host))
- rqst.CookieContainer = WebPage.webcookies[m_uri.Host];
- else
- {
- CookieContainer cc = new CookieContainer();
- WebPage.webcookies[m_uri.Host] = cc;
- rqst.CookieContainer = cc;
- }
- }
- HttpWebResponse rsps = (HttpWebResponse)rqst.GetResponse();
- Stream sm = rsps.GetResponseStream();
- if (!rsps.ContentType.ToLower().StartsWith("text/") || rsps.ContentLength > 1 << 22)
- {
- rsps.Close();
- m_good = false;
- return;
- }
- Encoding cding = System.Text.Encoding.Default;
- string contenttype = rsps.ContentType.ToLower();
- int ix = contenttype.IndexOf("charset=");
- if (ix != -1)
- {
- try
- {
- cding = System.Text.Encoding.GetEncoding(rsps.ContentType.Substring(ix + "charset".Length + 1));
- }
- catch
- {
- cding = Encoding.Default;
- }
- //该处视情况而定 有的需要解码
- //m_html = HttpUtility.HtmlDecode(new StreamReader(sm, cding).ReadToEnd());
- m_html = new StreamReader(sm, cding).ReadToEnd();
- }
- else
- {
- //该处视情况而定 有的需要解码
- //m_html = HttpUtility.HtmlDecode(new StreamReader(sm, cding).ReadToEnd());
- m_html = new StreamReader(sm, cding).ReadToEnd();
- Regex regex = new Regex("charset=(?<cding>[^=]+)?\"", RegexOptions.IgnoreCase);
- string strcding = regex.Match(m_html).Groups["cding"].Value;
- try
- {
- cding = Encoding.GetEncoding(strcding);
- }
- catch
- {
- cding = Encoding.Default;
- }
- byte[] bytes = Encoding.Default.GetBytes(m_html.ToCharArray());
- m_html = cding.GetString(bytes);
- if (m_html.Split(‘?‘).Length > 100)
- {
- m_html = Encoding.Default.GetString(bytes);
- }
- }
- m_pagesize = m_html.Length;
- m_uri = rsps.ResponseUri;
- rsps.Close();
- }
- catch (Exception ex)
- {
- }
- }
- public WebPage(string _url)
- {
- string uurl = "";
- try
- {
- uurl = Uri.UnescapeDataString(_url);
- _url = uurl;
- }
- catch { };
- Init(_url);
- }
- #endregion
- }
- /// <summary>
- /// 主程序编写作者:大黑
- /// (WebPage类编写者另有其人,类Link的定义在他博文的留言区,这是他的博文地址http://blog.csdn.net/yysyangyangyangshan/article/details/6661886)
- /// 描述:由C#编写的多线程异步抓取网页的网络爬虫控制台程序
- /// 功能:目前只能提取网络链接,所用的两个记录文件并不需要很大。网页文本、图片、视频和html代码暂时不能抓取,请见谅。
- /// 但需要注意,网页的数目是非常庞大的,如下代码理论上大概可以把整个互联网网页链接都抓下来。
- /// 但事实上,由于处理器功能和网络条件(主要是网速)限制,一般的家用电脑最多能胜任12个线程左右的抓取任务,抓取速度有限。可以抓取,但需要时间和耐心。
- /// 当然,这个程序把所有链接抓下来是可能的,因为链接占系统空间并不多,而且有记录文件的帮助,已抓取网页的数量可以堆积下去,
- /// 甚至可以把所有的互联网网络链接都存取下来,当然,最好是分批次。建议设置maxNum为500-1000左右,慢慢累积下去。
- /// 另外因为是控制台程序,有时候显示字符过多会系统会暂停显示,这时候只要点击控制台按下回车键就可以了。程序假死的时候,可以按回车键(Enter)试试。
- /// 使用本程序,请确保已创建相应的记录文件,出于简化代码的考虑,本程序做的并不健壮,请见谅。
- /// 默认的文件创建在E盘根目录“已抓取网址.txt”和“待抓取网址.txt”这两个文本文件中,使用者需要自行创建这两个文件,注意后缀名不要搞错。
- /// 这两个文件里面的链接基本都是有效链接,可以单独处理使用。
- /// 本爬虫程序的速度如下:
- /// 10线程最快大概400个链接每分钟
- /// 6-8线程最快大概200-300个链接每分钟
- /// 2-4线程最快大概150-200个链接每分钟
- /// 单线程最快大概70-100个链接每分钟
- /// 之所以用多线程异步抓取完全是出于效率考虑,本程序多线程同步并不能带来速度的提升,只要抓取的网页不要太多重复和冗余就可以,异步并不意味着错误。
- /// </summary>
- class Program
- {
- //默认的种子网址,可以改动。尽量保持不同的网址,可以提高效率。
- //另外注意改的时候“,”符号要注意,别改错了,要英文逗号。
- //默认是3线程3个种子网址,最多12线程12个网址,如果要12个以上,可以自己在后面添加。线程设定为12个以上时,必须添加网址,不然会出错
- //每个网址对应一个线程,即6线程对应6网址,12线程对应12网址,改默认值的时候要注意parts和数组linkArray的对应关系。
- //实测当CPU是i5处理器时,最多运行8-10线程,会伴有严重的卡顿。线程数越高,对CPU要求越高。一般CPU 2-4线程就可以。
- static string[] linkArray = {"http://www.163.com/","http://www.sohu.com/","http://www.srcfans.com"};
- //设定存放已抓取网址列表的文件路径
- static string urlCapturedDir = @"E:\已抓取网址.txt";
- //设定存放未抓取网址列表的文件路径
- static string myLinkDir = @"E:\待抓取网址.txt";
- //同时抓取网址的线程数
- private static int parts=4;
- //目前抓取的网页数量
- private static int count=0;
- //设定的最多抓取网页的数量
- private static int maxNum=2000;
- //待抓取的网址链表
- private static List<string> myLink=new List<string>();
- //已抓取的网址链表
- private static List<string> urlCaptured=new List<string>();
- //用于临时存放待抓取的某一个网址
- private static string strLink = "";
- public Program(string link)
- {
- myLink.Add(link);
- }
- public void doWork()
- {
- Console.WriteLine("working...");
- while ((myLink.Count != 0) && (count < maxNum))
- {
- strLink = myLink[0];
- if (!urlCaptured.Contains(strLink))
- {
- //加入已抓取队列
- urlCaptured.Add(strLink);
- //当前抓取的网页数量
- count++;
- //通过WebPage类抓取
- WebPage tempWeb = new WebPage(strLink);
- Console.WriteLine("网址" + strLink + "共有" + tempWeb.Links.Count + "个链接");
- foreach (Link li in tempWeb.Links)
- {
- //确保不重复抓取
- if (!myLink.Contains(li.NavigateUrl))
- myLink.Add(li.NavigateUrl);
- }
- Console.WriteLine("待抓取网页的数目是:" + myLink.Count);
- //确保不重复抓取,此句多线程运行会报错
- while(myLink.Remove(strLink));
- }
- else
- {
- //删除重复网址
- while (myLink.Remove(strLink)) ;
- }
- Console.WriteLine("目前共抓取了" + count + "个网页");
- }
- }
- static void printLinks(List<string> links)
- {
- foreach(string s in links)
- {
- Console.WriteLine(s);
- }
- }
- static void Main(string[] args)
- {
- //string seedUrl = "http://www.srcfans.com/";
- //WebPage webInfo = new WebPage(seedUrl);
- //Console.WriteLine( webInfo.Context);//不包含html标签的所有内容
- //Console.WriteLine( webInfo.M_html);//包含html标签的内容
- //urlCaptured.Add(seedUrl);
- //读取已处理网址列表(urlCaptured)
- string[] lines = System.IO.File.ReadAllLines(urlCapturedDir);
- int urlCapturedIndex = 0;
- foreach (string line in lines)
- {
- //if (!urlCaptured.Contains(line))
- {
- urlCaptured.Add(line);
- urlCapturedIndex++;
- if(urlCapturedIndex%2000==0)
- {
- Console.WriteLine("已导入" + urlCapturedIndex + "项已抓取网址");
- }
- }
- }
- // 显示已抓取网址列表
- Console.WriteLine("已读取已处理网址列表,共"+urlCaptured.Count+"条信息:");
- //foreach (string line in urlCaptured)
- //{
- // Console.WriteLine(line);
- //}
- //Console.WriteLine("已处理网址列表显示完毕");
- //未抓取网址初始化
- string[] lines2 = System.IO.File.ReadAllLines(myLinkDir);
- int myLinkIndex = 0;
- foreach (string line in lines2)
- {
- //Contains方法太耗时
- //if (!myLink.Contains(line))
- {
- myLink.Add(line);
- myLinkIndex++;
- if(myLinkIndex%2000==0)
- {
- Console.WriteLine("已导入" + myLinkIndex + "项待抓取网址");
- }
- }
- }
- // 显示未抓取网址列表
- Console.WriteLine("已读取未抓取网址列表,共" + myLink.Count + "条信息:");
- //foreach (string line in myLink)
- //{
- // Console.WriteLine(line);
- //}
- //Console.WriteLine("未抓取网址列表显示完毕");
- System.Threading.Thread[] threads = new System.Threading.Thread[parts];
- for (int i = 0; i < parts; i++)
- {
- string str_l = linkArray[i];
- Program p = new Program(str_l);
- System.Threading.Thread t = new System.Threading.Thread(new System.Threading.ThreadStart(p.doWork));
- threads[i] = t;
- threads[i].Name = "Thread" + i.ToString();
- }
- for (int i = 0; i < parts; i++)
- {
- threads[i].Start();
- }
- //为了确保 Main 函数不会尝试在辅助线程有机会执行结束之前将它终止
- //Main 函数将一直循环,直到辅助线程对象的 IsAlive 属性设置为 false
- //必须用while,表示线程都已经执行完了
- for (int i = 0; i < parts; i++)
- {
- while (threads[i].IsAlive)
- {
- ;
- }
- }
- Console.WriteLine("一共抓取了" + urlCaptured.Count + "个网址");
- Console.WriteLine("待处理的网址共有:" + myLink.Count + "个");
- Console.WriteLine("检查重复项....");
- List<string> temp_l = new List<string>();
- foreach (string str in urlCaptured)
- {
- if (!temp_l.Contains(str))
- {
- temp_l.Add(str);
- }
- else
- {
- Console.WriteLine("网址" + str + "重复");
- }
- }
- Console.WriteLine("共有" + (urlCaptured.Count - temp_l.Count) + "项是重复网址");
- urlCaptured = temp_l;
- Console.WriteLine("已抓取网址写入文件...");
- //对已抓取的网址进行排序
- urlCaptured.Sort();
- using (System.IO.StreamWriter file =
- new System.IO.StreamWriter(urlCapturedDir))
- {
- foreach(string s in urlCaptured)
- {
- file.WriteLine(s);
- }
- }
- Console.WriteLine("已抓取网址写入完成");
- Console.WriteLine("待处理网址写入文件...");
- myLink.Sort();
- using (System.IO.StreamWriter file =
- new System.IO.StreamWriter(myLinkDir))
- {
- foreach (string s in myLink)
- {
- file.WriteLine(s);
- }
- }
- Console.WriteLine("待抓取网址写入完成");
- //下面的句子表示保持显示当前控制台命令行,不然控制台会一闪而过
- Console.WriteLine("按任意键退出...");
- Console.ReadKey();
- }
- }
- }
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