wIndows phone 7 解析Html数据

原文:wIndows phone 7 解析Html数据

在我的上一篇文章中我介绍了windows phone 7的gb2312解码,

http://www.cnblogs.com/qingci/archive/2011/11/25/2263124.html

解决了下载的Html乱码问题,这一篇,我将介绍关于windows phone 7解析html数据，以便我们获得想要的数据.

这里,我先介绍一个类库HtmlAgilityPack,（上一篇文章也是通过这个工具来解码的）. 类库的dll文件我会随demo一起提供

这里,我以新浪新闻为例来解析数据

先看看网页版的新浪新闻

http://news.sina.com.cn/w/sd/2011-11-27/070023531646.shtml

然后我们看一下他的源文件，

发现新闻内容的结构是

<div class="blkContainerSblk">
				<h1 id="artibodyTitle" pid="1" tid="1" did="23531646" fid="1666">title</h1>
				<div class="artInfo"><span id="art_source"><a href="http://www.sina.com.cn">http://www.sina.com.cn</a></span>  <span id="pub_date">pub_date</span>  <span id="media_name"><a href="">media_name</a> <a href=""></a> </span></div>

				<!-- 正文内容 begin -->
				<!-- google_ad_section_start -->

				<div class="blkContainerSblkCon" id="artibody"></div>
</div>

大部分还有ID属性,这更适合我们去解析了。

接下来我们开始去解析

第一： 引用HtmlAgilityPack.dll文件

第二：用WebClient或者WebRequest类来下载HTML页面然后处理成字符串。

 public  delegate void CallbackEvent(object sender, DownloadEventArgs e);
        public  event CallbackEvent DownloadCallbackEvent;
        public void HttpWebRequestDownloadGet(string url)
        {

            Thread _thread = new Thread(delegate()
            {
                Uri _uri = new Uri(url, UriKind.RelativeOrAbsolute);
                HttpWebRequest _httpWebRequest = (HttpWebRequest)WebRequest.Create(_uri);
                 _httpWebRequest.Method="Get";

                _httpWebRequest.BeginGetResponse(new AsyncCallback(delegate(IAsyncResult result)
                {
                    HttpWebRequest _httpWebRequestCallback = (HttpWebRequest)result.AsyncState;
                    HttpWebResponse _httpWebResponseCallback = (HttpWebResponse)_httpWebRequestCallback.EndGetResponse(result);
                    Stream _streamCallback = _httpWebResponseCallback.GetResponseStream();

                    StreamReader _streamReader = new StreamReader(_streamCallback,new HtmlAgilityPack.Gb2312Encoding());
                    string _stringCallback = _streamReader.ReadToEnd();

                    Deployment.Current.Dispatcher.BeginInvoke(new Action(() =>
                    {
                        if (DownloadCallbackEvent != null)
                        {
                            DownloadEventArgs _downloadEventArgs = new DownloadEventArgs();
                            _downloadEventArgs._DownloadStream = _streamCallback;
                            _downloadEventArgs._DownloadString = _stringCallback;
                            DownloadCallbackEvent(this, _downloadEventArgs);

                        }
                    }));

                }), _httpWebRequest);
            }) ;
            _thread.Start();
        }
       // }

O(∩_∩)O! 我这个比较复杂, 总之我们下载了html的数据就行了。  

贴一个简单的下载方式吧

WebClient webClenet=new WebClient();  

         webClenet.Encoding = new HtmlAgilityPack.Gb2312Encoding(); //加入这句设定编码  

         webClenet.DownloadStringAsync(new Uri("http://news.sina.com.cn/s/2011-11-25/120923524756.shtml", UriKind.RelativeOrAbsolute));       

         webClenet.DownloadStringCompleted += new DownloadStringCompletedEventHandler(webClenet_DownloadStringCompleted);

 现在处理回调函数的 e.Result

 string _result = e._DownloadString;

            HtmlDocument _doc = new HtmlDocument(); //实例化HtmlAgilityPack.HtmlDocument对象
            _doc.LoadHtml(_result);         //载入HTML

            HtmlNode _htmlNode01 = _doc.GetElementbyId("artibodyTitle");  //新闻标题的Div
            string _title = _htmlNode01.InnerText;

            HtmlNode _htmlNode02 = _doc.GetElementbyId("artibody");     //获取内容的div
            string _content = _htmlNode02.InnerText;
           // int _count= _htmlNode02.ChildNodes.Where(new Func<HtmlNode,bool>("div"));
            int _divIndex = _content.IndexOf(" .blkComment");

            _content= _content.Substring(0,_divIndex);

            #region　新浪标签
            HtmlNode _htmlNodo03 = _doc.GetElementbyId("art_source");
            string _www = _htmlNodo03.FirstChild.InnerText;
            string _wwwInt = _htmlNodo03.FirstChild.Attributes[0].Value;
            #endregion
            // string _source = _htmlNodo03;
            //_htmlNodo03.ChildNodes

            #region 发布时间
            HtmlNode _htmlNodo04 = _doc.GetElementbyId("pub_date");
            string _pub_date = _htmlNodo04.InnerText;
            #endregion

            #region 来源网站信息
            HtmlNode _htmlNodo05 = _doc.GetElementbyId("media_name");
            string _media_name = _htmlNodo05.FirstChild.InnerText;
            string _modia_source = _htmlNodo05.FirstChild.Attributes[0].Value;
            #endregion

            Media_nameHyperlinkButton.Content = _pub_date + " " + _media_name;
            Media_nameHyperlinkButton.NavigateUri = new Uri(_modia_source, UriKind.RelativeOrAbsolute);
            TitleTextBlock.Text = _title;
            ContentTextBlock.Text = _content;

结果如下图所示：

网页的大部分标签是没有ID属性的,不过幸运的是HtmlAgilityPack支持XPath

那就需要通过XPATH语言来查找匹配所需节点

XPath教程：http://www.w3school.com.cn/xpath/index.asp

案例下载：

http://115.com/file/dn87dl2d#
MyFramework_Test.zip