href= 正则表达式

获取网页的新闻连接:

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;
namespace WebApplication4
{
    public partial class _Default : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            string strNewsUrl = ConfigurationSettings.AppSettings["NewsUrl"];
            string strHTML = DownLoadHtml(strNewsUrl);

            int begin = 0;
            string strBegin = ConfigurationSettings.AppSettings["BeginStr"];
            string strEnd = ConfigurationSettings.AppSettings["EndStr"];
            string strContent = "";
            if (strBegin.Trim() != "" && strEnd.Trim() != "")
                strContent = GetHTMLContent(strHTML, strBegin, strEnd, ref begin);
            else
                strContent = strHTML;
            MatchCollection ms = GetUrlFromHtml(strContent);
           if (ms.Count > 0)
                {
                    Response.Write("<marquee onmouseover=this.stop() onmouseout=this.start() scrollDelay=110 class=a><font color=#ff0000>最新消息:</font>");

                    foreach (Match m in ms)
                    {
                        if (m.Groups[1].Value.Trim() != "" && m.Groups[3].Value.Trim() != "")
                        {

                           string href = string.Format("<a href='{0}' title='{2}'  target='_blank'>{1}</a>&nbsp;&nbsp;&nbsp;&nbsp;", m.Groups[1].Value.Trim(), m.Groups[3].Value.Trim(), m.Groups[3].Value.Trim());

                            Response.Write(href);
                        }
                    }
                    Response.Write("</marquee>");
                }
        }
      
        #region 获取网页内容

        public static string DownLoadHtml(string url)
        {
            string output = "";
            Encoding encode = Encoding.UTF8;
            WebClient webclient = new WebClient();
            //System.Net.GlobalProxySelection.Select = System.Net.GlobalProxySelection.GetEmptyWebProxy();

            try
            {
　　　　　　　　//如果使用代理上网,则使用如下方法,默认是使用IE代理设置
               //webclient.Proxy = new WebProxy("192.168.8.1", 808);
                webclient.Headers.Add("Referer", url);

                byte[] buff = webclient.DownloadData(url);
                output = encode.GetString(buff);
            }
            catch
            {
            }
            return output;
        }

        public static string GetHTMLContent(string strTarget, string strBegin, string strEnd, ref int begin)
        {
            string result;
            int posBegin, posEnd;
            posBegin = strTarget.IndexOf(strBegin, begin);
            if (posBegin != -1)
            {
                posEnd = strTarget.IndexOf(strEnd, posBegin + strBegin.Length);
                if (posEnd > posBegin)
                {
                    result = strTarget.Substring(posBegin, posEnd + strEnd.Length - posBegin);
                    begin = posEnd + strEnd.Length;
                    return result;

                }
            }
            begin = -1;
            return "";
        }

        //过滤特殊字符
        public static string RepalceStr(string str)
        {

            str = str.Replace("\r\n", "");
            str = str.Replace("\"", "");
            str = str.Replace("：", "");
            str = str.Replace("\t", "");
            str = str.Replace("&nbsp;", "");
            str = str.Replace("'", "");
            str = str.Replace("\r", "");
            str = str.Replace("\n", "");
            return str;
        }

        public static MatchCollection GetUrlFromHtml(string strContent)
        {
            //string regex = @"\<a.*href\s*=\s*(?:""(?<url>[^""]*)""|'(?<url>[^']*)'|(?<url>[^\>^\s]+)).*\>(?<title>[^\<^\>]*)\<[^\</a\>]*/a\>";
            //string regex = @"\<a.*href\s*=\s*(?:""(?<url>[^""]*)""|'(?<url>[^']*)'|(?<url>[^\>^\s]+)).*\>(?<title>[^\<^\>]*)\<[^\</a\>]*/a\>";
            //string regex = @"\<a.*href\s*=\s*(?:""(?<url>[^""]*)""|'(?<url>[^']*)'|(?<url>[^\>^\s]+))\s*(.*)\s*title=[""|'](?<remarktext>[\s\S])[""|'].*\>(?<title>[^\<^\>]*)\<[^\</a\>]*/a\>";

            //string regex= "href=\"(?<url>[\\s\\S]*?)\"[\\s\\S]title=\"(?<remarktext>[\\s\\S]*?)\"[\\s\\S]*?>(?<title>[\\s\\S]*?)</a>";
            //string regex = "<a.*href\\s*=\\s*(?:\"(?<url>[^\"]*)\"|'(?<url>[^']*)'|(?<url>[^\\>^\\s]+)).*\\>[\\s\\S]title=\"(?<remarktext>[\\s\\S]*?)\"[\\s\\S]*?>(?<title>[\\s\\S]*?)</a>"; 

            //string regex = "href=\"(?<url>[\\s\\S]*?)\"[\\s\\S]*?title=\"(?<remarktext>[\\s\\S]*?)\"[\\s\\S]*?>(?<title>[\\s\\S]*?)</a>";
            //string regex = "href=['|\"](?<url>[\\s\\S]*?)['|\"][\\s\\S]*?title='(?<remarktext>[\\s\\S]*?)'[\\s\\S]*?>(?<title>[\\s\\S]*?)</a>";

            //string regex = "href=(\'|\\\\\")(?<url>[\\s\\S]*?)(\'|\\\\\")[\\s\\S]*?title=\\\\\"(?<remarktext>[\\s\\S]*?)\\\\\"[\\s" +"\\S]*?>(?<title>[\\s\\S]*?)</a>";
            string regex = "<a[\\s]+href[\\s]*=[\\s]*\"([^<\"]+)\" target=\"([^<\"]+)\" title=\"([^<\"]+)\"><span class=\"([^<\"]+)\">([^<\"]+)</span></a>";  
          
            //string p = "href=[\"](?<url>[\\s\\S]*?)[\"][\\s\\S]*?title='(?<remarktext>[\\s\\S]*?)'[\\s\\S]*?>(?<title>[\\s\\S]*?)</a>";

            Regex reg = new Regex(regex, RegexOptions.IgnoreCase);
            MatchCollection ms = reg.Matches(strContent);
            return ms;

        }

        public static string GetNewsUrl()
        {
            if (ConfigurationSettings.AppSettings["NewsUrl"] == "")
                return "";
            else
                return "../desktop/getnewsUrl.aspx";

        }
        #endregion
    }
}

web.config源码:

    <appSettings>
        <!--新闻获取网址-->
        <add key="NewsUrl" value="http://jyj.cixi.gov.cn/"/>
        <add key="BeginStr" value="var teshu_shu = 1;"/>
        <add key="EndStr" value="/script"/>
        <add key="expressMatch"/>
       </appSettings>