从网页中抓取信息的问题

我正在做一个投标管理系统
比如：下面是一个招标网
http://www.szft.gov.cn/zfbm/zfcg/zhbgg/index.jsp
点击进去是详细内容现在我要抓取里面有用的招标信息，要如何抓取呀。
请各位网友提供一个思路呀。谢了。

解决方案 »

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帮忙http://community.csdn.net/Expert/topic/4999/4999993.xml?temp=.1140558
用传参数的方法，在接收的页面里用string id = Request["ID"]来接收
private string GrabContent( string strProperty, string str, string strReg )
 {
 Regex reg = new Regex( strReg, RegexOptions.IgnoreCase);
 Match m = reg.Match( str );
 return m.Groups[strProperty].Value;
 /*
 MatchCollection mc = reg.Matches(str);
 foreach(Match m in mc )
 {
 string name = m.Groups[strProperty].Value;
 }
 return string.Empty;
 */
 } private string GrabUrl( string url )
 {
 WebClient wc = new WebClient();
 Stream s = null;
 try
 {
 s = wc.OpenRead(url);
 StreamReader sr = new StreamReader( s, System.Text.Encoding.Default);
 return sr.ReadToEnd();
 }
 catch
 {
 return string.Empty;
 }
 finally
 {
 if( s != null )
 s.Close();
 wc.Dispose();
 }
 } const string categoryUrl = "http://www.lijiabaobei.com/category.asp?cid={0}";
 const string subcategoryUrl = "http://www.lijiabaobei.com/scategory.asp?cid={0}";
 const string subcategoryPageUrl = "http://www.lijiabaobei.com/scategory.asp?page={0}&cid={1}";
 const string productUrl = "http://www.lijiabaobei.com/product.asp?cid={0}"; const string subcategoryReg = "<td valign=\"bottom\" bgcolor=\"E7E7E7\" style=\"padding-top:4px;padding-left:8px\">·<a href=\"scategory.asp\\?cid=(?<subcategoryid>.*?)\">(?<name>.*?)</a></td>"; const string subcategoryPage = "第1/(?<pagecount>.*?)页";
 const string productLink = "<td width=\"293\" valign=\"bottom\" class=\"large\" style=\"padding-top:12px\"><a class=\"nav_sp_title_l\" href=\"product.asp\\?cid=(?<id>.*?)\">(?<name>.*?)</a></td>";

 private void Button1_Click(object sender, System.EventArgs e)
 {
 /*
 using (SqlDataReader dr = lsy.GetAllCategory())
 {
 while(dr.Read())
 {
 Regex reg = new Regex( subcategoryReg, RegexOptions.IgnoreCase );
 string html = GrabUrl( string.Format( categoryUrl, dr["categoryid"] ) );
 MatchCollection mc = reg.Matches( html ); for( int i = 0; i < mc.Count; i++ )
 {
 Match m = mc[i]; lsy.AddSubCategory( Int32.Parse(dr["categoryid"].ToString()),
 Int32.Parse(m.Groups["subcategoryid"].Value.Trim()),
 m.Groups["name"].Value.Trim()
 );
 }
 }
 }
 */ using ( SqlDataReader dr = lsy.GetAllSubCategory())
 {
 while(dr.Read())
 {
 int subcategoryid = Int32.Parse(dr["subcategoryid"].ToString() );
 string html = GrabUrl( string.Format( subcategoryUrl, subcategoryid ) ); Regex regPage = new Regex(subcategoryPage, RegexOptions.IgnoreCase );
 Match mp = regPage.Match(html); int pageCount = Convertor.ToInt32(mp.Groups["pagecount"].Value.Trim()); /* ParseOnePage( html, subcategoryid ); for( int i = 1; i < pageCount; i++ )
 {
 ParseOnePage( GrabUrl( string.Format( subcategoryPageUrl, i, subcategoryid ) ), subcategoryid);
 }
 */ for( int i = 2; i <= pageCount; i++ )
 ParseOnePage( GrabUrl( string.Format( subcategoryPageUrl, i, subcategoryid ) ), subcategoryid); }
 }
 } private void ParseOnePage(string html, int subcategoryid )
 {
 //获取子项
 Regex reg = new Regex( productLink, RegexOptions.IgnoreCase );
 MatchCollection mc = reg.Matches( html ); for( int i = 0; i < mc.Count; i++ )
 {
 Match m = mc[i]; int id = Int32.Parse(m.Groups["id"].Value.Trim()); AddProduct(id, subcategoryid);
 }
 } const string regProducingArea = " \r\n ·产地/(?<producingarea>.*?) </td>\r\n";
 const string regAge = "适用月(年)龄:(?<age>.*?)";
 const string regIntroduction = "★(?<introduction>.*?)</td>\r\n";
 const string regRe = "<td style=\"padding:10px 5px 10px 13px\">(?<re>.*?)\r\n</td>\r\n\t\t\t\t\t\t</tr>\r\n\t </table>";
 const string regRow = "<td>(?<number>.*?)</td>\r\n\t\t\t\t\t\t\t\t<td>(?<name>.*?)</td>\r\n\t\t\t\t\t\t\t\t<td>(?<spec>.*?)</td>\r\n\t\t\t\t\t\t\t\t<td>￥(?<etprice>.*?)</td>\r\n\t\t\t\t\t\t\t\t<td>￥(?<vipprice>.*?)</td>";
 const string regImage = "<img src=\"(?<image>.*?)\" width=\"200\" height=\"200\" border=\"0\" class=\"box_juti\"></a> \r\n";
 const string regSpec = "<td colspan=\"2\" valign=\"top\" style=\"padding-top:10px;padding-bottom:20px\">\r\n ·规格/(?<spec>.*?)\r\n"; private void AddProduct( int id, int subcategoryid )
 {
 string htmlProduct = GrabUrl( string.Format( productUrl, id ) ); string name;
 string spec;
 string number;
 decimal etprice;
 decimal vipprice; GetRowsProperty( htmlProduct, out number, out name, out spec, out etprice, out vipprice ); string producingarea = GetProperty(htmlProduct, regProducingArea, "producingarea");
 string age = GetProperty(htmlProduct, regAge, "age");
 string introduction = GetProperty(htmlProduct, regIntroduction, "introduction");
 string re = GetProperty(htmlProduct, regRe, "re");
 string image = GetProperty(htmlProduct, regImage, "image");

 spec = GetProperty(htmlProduct, regSpec, "spec" ); lsy.AddProduct(id, subcategoryid,
 name,
 number,
 spec,
 producingarea,
 age,
 introduction,
 re,
 image,
 etprice,
 vipprice);
 }