C#页面抓取信息

//根据Url地址得到网页的html源码private string GetWebContent(string Url){string strResult="";try{HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);//声明一个HttpWebRequest请求request.Timeout = 30000;//设置连接超时时间request.Headers.Set("Pragma", "no-cache");HttpWebResponse response = (HttpWebResponse)request.GetResponse();Stream streamReceive = response.GetResponseStream();Encoding encoding = Encoding.GetEncoding("GB2312");StreamReader streamReader = new StreamReader(streamReceive, encoding);strResult = streamReader.ReadToEnd();}catch{MessageBox.Show("出错");}return strResult;}为了使用HttpWebRequest和HttpWebResponse，需填名字空间引用using ;以下是程序具体实现过程：private void button1_Click(object sender, EventArgs e){//要抓取的URL地址string Url = "http://list./topso/mp3topsong.html?id=1#top2";//得到指定Url的源码string strWebContent = GetWebContent(Url);richTextBox1.Text = strWebContent;//取出和数据有关的那段源码int iBodyStart = strWebContent.IndexOf("<body", 0);int iStart = strWebContent.IndexOf("歌曲TOP500", iBodyStart);int iTableStart = strWebContent.IndexOf("<table", iStart);int iTableEnd = strWebContent.IndexOf("</table>", iTableStart);string strWeb = strWebContent.Substring(iTableStart, iTableEnd - iTableStart + 8);//生成HtmlDocumentWebBrowser webb = new WebBrowser();webb.Navigate("about:blank");HtmlDocument htmldoc = webb.Document.OpenNew(true);htmldoc.Write(strWeb);HtmlElementCollection htmlTR = htmldoc.GetElementsByTagName("TR");foreach (HtmlElement tr in htmlTR){string strID = tr.GetElementsByTagName("TD")[0].InnerText;string strName = SplitName(tr.GetElementsByTagName("TD")[1].InnerText, "MusicName");string strSinger = SplitName(tr.GetElementsByTagName("TD")[1].InnerText, "Singer");strID = strID.Replace(".", "");//插入DataTableAddLine(strID, strName, strSinger,"0");string strID1 = tr.GetElementsByTagName("TD")[2].InnerText;string strName1 = SplitName(tr.GetElementsByTagName("TD")[3].InnerText, "MusicName");string strSinger1 = SplitName(tr.GetElementsByTagName("TD")[3].InnerText, "Singer");//插入DataTablestrID1 = strID1.Replace(".", "");AddLine(strID1, strName1, strSinger1,"0");string strID2 = tr.GetElementsByTagName("TD")[4].InnerText;string strName2 = SplitName(tr.GetElementsByTagName("TD")[5].InnerText, "MusicName");string strSinger2 = SplitName(tr.GetElementsByTagName("TD")[5].InnerText, "Singer");//插入DataTablestrID2 = strID2.Replace(".", "");AddLine(strID2, strName2, strSinger2,"0");}//插入数据库InsertData(dt);dataGridView1.DataSource = dt.DefaultView;}