string str="wecncnc<a href=\"list.asp?Page=1&boardid=33&t=656727&p=11&tp=%B9%AB%BF%AAICSI%B5%C4MP3%B7%BD%B0%B8%C9%E8%BC%C6\">下一页</a>";
str+="wecncnc<a href=\"listww.asp?Page=1&boardid=33&t=656727&p=11&tp=%B9%AB%BF%AAICSI%B5%C4MP3%B7%BD%B0%B8%C9%E8%BC%C6\">下一页</a>";
Regex re = new Regex("<a[^>]+href=""(?<url>[^""]+)""",RegexOptions.IgnoreCase);
Match m = re.Match(str);
if (m.Success)
Console.WriteLine(m.Groups["url"].Value);
一段找出URL的代码（C#）
80酷酷网 80kuku.com
