HtmlWeb hw = new HtmlWeb();
            hw.DefaultEncoding = System.Text.Encoding.GetEncoding("gb2312");
            string url = @"http://bbs.99read.com";
            HtmlDocument doc = hw.Load(url);
            //doc.Save("mshome.htm");

            HtmlNodeCollection hrefs = doc.DocumentNode.SelectNodes("//a[@href]");

            if (hrefs.Count > 0)
            {
                foreach (HtmlNode href in hrefs)
                {
                    if (href.Attributes["href"].Value.Trim().StartsWith("index.asp?boardid="))
                    {
                        Console.WriteLine(href.InnerText + ":" + href.Attributes["href"].Value);
                    }
                }
            }

            Console.ReadKey();