读懂正则表达式就这么简单

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    <span class="diggnum" id="digg_count_3439076">4</span>
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    <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" /></a>    在项目开发过程中，如何有序的保存项目中的各类数据文件，建立一个分类清晰、方便管理的目录结构是非常重要的。 综合以前的项目和一些朋友的项目结构，我整理了一份我觉得还不错的项目目录结构。 在这里分享给大家，欢迎各位提出你宝贵的意见和建议。如果喜欢请“推荐”则个，感激万分！！ 整个目录设置到4级子目录，实... 
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    <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" title="2013-11-23 16:40" class="gray">
        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>
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    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=http://www.mamicode.com/"(?<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=http://www.mamicode.com/"(?<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; }

    }