求正则！！！

[Mirror然]

<h3 class="summary"><a stat="lf_aclog=1-17463315668-44-all|-1-142.80&lf_acfrom=0&at_alitrackid=&stats_click=user_group%3A-0_0-0_0_0_0_0_0---1-0--1-%
3Bscreen_size%3A0&rn=9da13c112babf687791a80fb40addd02" href="http://ju.mmstat.com/?url=http://detail.tmall.com/item.htm?id=17463315668&ad_id=&am_id=&cm_id=&pm_id=1501047141786640d61d" target="_blank" class="EventCanSelect" title="OSA2013春装新款女装上衣时尚雪纺小衫打底衫女T恤女长袖T32003">OSA2013春装新款女装<span class=H>上衣</span>时尚雪纺小衫打底衫女T恤女长袖T32003</a>

上面是抓取淘宝的数据

想获取href内的链接 中的ID值 id=17463315668
获取HREF内的链接也行 不想再拆分

[骑着蜗牛去爬山]

string str = File.ReadAllText("D:\\1.txt", Encoding.Default);
            str = Regex.Match(str, @"(?is)(?<=href=[""'][^>""']*?id=)\d+(?=&|[""'])").Value;
            Console.WriteLine(str);