高手请进:一个很奇怪的问题（详尽表述，准备好一切环境，只等高手解答）

我这个页面是想远程抓取一个给定URL的网页的一部分内容（例如某个div里的内容），用到了正则表达式，我的抓取页面很简单。如下：<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Test.aspx.cs" Inherits="ToHtml.Test" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>无标题页</title>
</head>
<body>
    <form id="form1" runat="server">
    <div></div>
    </form>
</body>
</html>
Test.aspx.cs里的内容是：using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Text.RegularExpressions;
using System.Text;
using System.Net;
using System.IO;
using System.Xml;namespace ToHtml
{
    public partial class Test : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.Load(Server.MapPath("Setting.xml"));            XmlNode node1 = xmlDoc.SelectSingleNode("/root/HttpAdress");
            XmlNode node2 = xmlDoc.SelectSingleNode("/root/RegexExpression");            string HttpAdress = node1.InnerText;            string RexFat = node2.InnerText;            Encoding code = Encoding.GetEncoding("UTF-8");
            StreamReader sr = null;
            string str = null;            //读取远程路径
            WebRequest temp = WebRequest.Create("http://localhost:1806/plat.htm");
            WebResponse myTemp = temp.GetResponse();
            sr = new StreamReader(myTemp.GetResponseStream(), code);
            //读取
            try
            {
                sr = new StreamReader(myTemp.GetResponseStream(), code);
                str = sr.ReadToEnd();
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                sr.Close();
            }            string StrC = str.Replace("\"", "");
            Regex reg = new Regex(RexFat);
            MatchCollection matches = reg.Matches(StrC);
            foreach (Match m in matches)
                Response.Write(m.Value);
        }
    }
}就是要页面一加载就执行！正则表达式在Setting.xml里，Setting.xml文件如下：<?xml version="1.0" encoding="utf-8" ?>
<root>
<HttpAdress><![CDATA[http://club.qikan.com/6/GroupIndex.aspx]]></HttpAdress>
<RegexExpression><![CDATA[<table cellspacing=0 border=0 id=_ctl0_MainContent_ExpandGroupIndex__ctl0_ExpandNewPosts__ctl0_NewPostDataGrid(?<content>.*?)</table>]]></RegexExpression>
</root>
要抓取的页面plat.htm如下:<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title>Untitled Page</title>
</head>
<body>
    <div>
        dajiahao</div>
    <table cellspacing="0" border="0" id="_ctl0_MainContent_ExpandGroupIndex__ctl0_ExpandNewPosts__ctl0_NewPostDataGrid"
        style="border-style: None; font-size: X-Small; height: 120px; border-collapse: collapse;">
        <tr>
            <td>
                <font color="#00329a" size="2">·</font> <a id="_ctl0_MainContent_ExpandGroupIndex__ctl0_ExpandNewPosts__ctl0_NewPostDataGrid__ctl2_NewPostsHyperLink"
                    href="/45195/ShowPost.aspx" target="_blank">打破完美世界</a>
            </td>
        </tr>
        <tr>
            <td>
                <font color="#00329a" size="2">·</font> <a id="_ctl0_MainContent_ExpandGroupIndex__ctl0_ExpandNewPosts__ctl0_NewPostDataGrid__ctl3_NewPostsHyperLink"
                    href="/45182/ShowPost.aspx" target="_blank">化妆品也会致癌？什么样的化妆品最安全？</a>
            </td>
        </tr>
        <tr>
            <td>
                <font color="#00329a" size="2">·</font> <a id="_ctl0_MainContent_ExpandGroupIndex__ctl0_ExpandNewPosts__ctl0_NewPostDataGrid__ctl4_NewPostsHyperLink"
                    href="/45178/ShowPost.aspx" target="_blank">化妆品节约省钱大法！</a>
            </td>
        </tr>
        <tr>
            <td>
                <font color="#00329a" size="2">·</font> <a id="_ctl0_MainContent_ExpandGroupIndex__ctl0_ExpandNewPosts__ctl0_NewPostDataGrid__ctl5_NewPostsHyperLink"
                    href="/45158/ShowPost.aspx" target="_blank">关于人类寿命大趋势的决定因素</a>
            </td>
        </tr>
        <tr>
            <td>
                <font color="#00329a" size="2">·</font> <a id="_ctl0_MainContent_ExpandGroupIndex__ctl0_ExpandNewPosts__ctl0_NewPostDataGrid__ctl6_NewPostsHyperLink"
                    href="/44904/ShowPost.aspx" target="_blank">小丽搭配 五类外套巧搭显瘦技巧</a>
            </td>
        </tr>
        <tr>
            <td>
                <font color="#00329a" size="2">·</font> <a id="_ctl0_MainContent_ExpandGroupIndex__ctl0_ExpandNewPosts__ctl0_NewPostDataGrid__ctl7_NewPostsHyperLink"
                    href="/44901/ShowPost.aspx" target="_blank">史上最牛逼的SUV，有钱不一定买得到</a>
            </td>
        </tr>
        <tr>
            <td>
                <font color="#00329a" size="2">·</font> <a id="_ctl0_MainContent_ExpandGroupIndex__ctl0_ExpandNewPosts__ctl0_NewPostDataGrid__ctl8_NewPostsHyperLink"
                    href="/44512/ShowPost.aspx" target="_blank">欧尚志*手袋站，国际名牌女士包包手袋批发集....</a>
            </td>
        </tr>
        <tr>
            <td>
                <font color="#00329a" size="2">·</font> <a id="_ctl0_MainContent_ExpandGroupIndex__ctl0_ExpandNewPosts__ctl0_NewPostDataGrid__ctl9_NewPostsHyperLink"
                    href="/44453/ShowPost.aspx" target="_blank">幽怨悲歌 中国历史上最能哭的五大女人 </a>
            </td>
        </tr>
    </table>
</body>
</html>看明白了吧？我要的就是抓取plat.htm的指定id的<table>里的内容，我看过，正则表达式好像没有配置错，但为什么就抓不到内容呢？谢谢各位，能帮我解答一下吗？

解决方案 »

  1.   


    string strPattern = @"你的正则表达式";
                MatchCollection Matches = Regex.Matches(plat.htm的内容, strPattern, RegexOptions.IgnoreCase | RegexOptions.Compiled);
                foreach (Match NextMatch in Matches)
                {
                    str = NextMatch.Groups["src"].Value.ToString().Trim();
                }这是我原来用的很好用
      

  2.   

    Regex reg = new Regex(RexFat);
    改为
    Regex reg = new Regex(RexFat, RegexOptions.Singleline);要加上RegexOptions.Singleline，改变.的含义，因为你的源文本里面有换行\n，\n一样要作为匹配结果。