读懂正则表达式就这么简单

<div class="post_item"><div class="digg"> <div class="diggit" onclick="DiggIt(3439076,120879,1)">  <span class="diggnum" id="digg_count_3439076">4</span> </div> <div class="clear"></div>  <div id="digg_tip_3439076" class="digg_tip"></div></div>  <div class="post_item_body"> <h3><a class="titlelnk" href="http://www.cnblogs.com/swq6413/p/3439076.html" target="_blank">分享完整的项目工程目录结构</a></h3>      <p class="post_item_summary"><a href="http://www.cnblogs.com/swq6413/" target="_blank"><img width="48" height="48" class="pfs" src="http://pic.cnitblog.com/face/142964/20131116170946.png" </p>     <div class="post_item_foot">      <a href="http://www.cnblogs.com/swq6413/" class="lightblue">七少爷</a>  发布于 2013-11-23 15:48  <span class="article_comment"><a href="http://www.cnblogs.com/swq6413/p/3439076.html#commentform"  评论(4)</a></span><span class="article_view"><a href="http://www.cnblogs.com/swq6413/p/3439076.html" class="gray">阅读(206)</a></span></div></div><div class="clear"></div></div>

class Program {  static void Main(string[] args)  {   string content = HttpUtility.HttpGetHtml();   HttpUtility.GetArticles(content);  } } internal class HttpUtility {  //默认获取第一页数据  public static string HttpGetHtml()  {   HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://www.cnblogs.com/");   request.Accept = "text/plain, */*; q=0.01";   request.Method = "GET";   request.Headers.Add("Accept-Language", "zh-cn,zh;q=0.8,en-us;q=0.5,en;q=0.3");   request.ContentLength = 0;   request.Host = "www.cnblogs.com";   request.UserAgent = "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.1 (KHTML, like Gecko) Maxthon/4.1.3.5000 Chrome/26.0.1410.43 Safari/537.1";   HttpWebResponse response = (HttpWebResponse)request.GetResponse();   Stream responStream = response.GetResponseStream();   StreamReader reader = new StreamReader(responStream, Encoding.UTF8);   string content = reader.ReadToEnd();   return content;  }  public static List<Article> GetArticles(string htmlString)  {   List<Article> articleList = new List<Article>();   Regex regex = null;   Article article = null;   regex = new Regex("<div class=/"post_item/">(?<content>.*?)(?=<div class=/"clear/">" + @"</div>/s*</div>)",        RegexOptions.Singleline);   if (regex.IsMatch(htmlString))   {    MatchCollection aritcles = regex.Matches(htmlString);    foreach (Match item in aritcles)    {     article = new Article();     //取推荐     regex =      new Regex(       "<div class=/"digg/">.*<span.*>(?<digNum>.*)" + @"</span>" +       ".*<div class=/"post_item_body/">", RegexOptions.Singleline);     article.DiggNum = regex.Match(item.Value).Groups["digNum"].Value;     //取文章标题 需要去除转义字符     regex = new Regex("<h3>(?<a>.*)</h3>", RegexOptions.Singleline);     string a = regex.Match(item.Value).Groups["a"].Value;     regex = new Regex("<a//s.*href=/"(?<href>.*?)/".*>(?<summary>.*)</a>", RegexOptions.Singleline);     article.AritcleUrl = regex.Match(a).Groups["href"].Value;     article.AritcleTitle = regex.Match(a).Groups["summary"].Value;     //取作者图片      regex = new Regex("<a.*>(?<img><img[^>].*>)</a>", RegexOptions.Singleline);     article.AuthorImg = regex.Match(item.Value).Groups["img"].Value;     //取作者博客URL及链接的target属性     regex = new Regex("<a//s*?href=/"(?<href>.*)/"//s*?target=/"(?<target>.*?)/">.*</a>",          RegexOptions.Singleline);     article.AuthorUrl = regex.Match(item.Value).Groups["href"].Value;     string urlTarget = regex.Match(item.Value).Groups["target"].Value;     //取文章简介     //1 先取summary Div中所有内容     regex = new Regex("<p class=/"post_item_summary/">(?<summary>.*)</p>", RegexOptions.Singleline);     string summary = regex.Match(item.Value).Groups["summary"].Value;     //2 取简介     regex = new Regex("(?<indroduct>(?<=</a>).*)", RegexOptions.Singleline);     article.AritcleInto = regex.Match(summary).Groups["indroduct"].Value;     //取发布人与发布时间     regex =      new Regex(       "<div class=/"post_item_foot/">//s*<a.*?>(?<publishName>.*)</a>(?<publishTime>.*)<span class=/"article_comment/">",       RegexOptions.Singleline);     article.Author = regex.Match(item.Value).Groups["publishName"].Value;     article.PublishTime = regex.Match(item.Value).Groups["publishTime"].Value.Trim();     //取评论数     regex =      new Regex(       "<span class=/"article_comment/"><a.*>(?<comment>.*)</a></span><span class=/"article_view/">",       RegexOptions.Singleline);     article.CommentNum = regex.Match(item.Value).Groups["comment"].Value;     //取阅读数     regex = new Regex("<span//s*class=/"article_view/"><a.*>(?<readNum>.*)</a>", RegexOptions.Singleline);     article.ReadNum = regex.Match(item.Value).Groups["readNum"].Value;     articleList.Add(article);    }   }   return articleList;  }  public static string ClearSpecialTag(string htmlString)  {   string htmlStr = Regex.Replace(htmlString, "/n", "", RegexOptions.IgnoreCase);   htmlStr = Regex.Replace(htmlStr, "/t", "", RegexOptions.IgnoreCase);   htmlStr = Regex.Replace(htmlStr, "/r", "", RegexOptions.IgnoreCase);   htmlStr = Regex.Replace(htmlStr, "/"", "'", RegexOptions.IgnoreCase);   return htmlStr;  } } public class Article {  /// <summary>  /// 文章标题  /// </summary>  public string AritcleTitle { get; set; }  /// <summary>  /// 文章链接  /// </summary>  public string AritcleUrl { get; set; }  /// <summary>  /// 文章简介  /// </summary>  public string AritcleInto { get; set; }  /// <summary>  /// 作者名  /// </summary>  public string Author { get; set; }  /// <summary>  /// 作者地址  /// </summary>  public string AuthorUrl { get; set; }  /// <summary>  /// 作者图片  /// </summary>  public string AuthorImg { get; set; }  /// <summary>  /// 发布时间  /// </summary>  public string PublishTime { get; set; }  /// <summary>  /// 推荐数  /// </summary>  public string DiggNum { get; set; }  /// <summary>  /// 评论数  /// </summary>  public string CommentNum { get; set; }  /// <summary>  /// 阅读数  /// </summary>  public string ReadNum { get; set; } }