想匹配html = <div class="back fl"><a href="javascript:void(0);" onclick="_gaq.push(['_trackEvent','function', 'onclick', 'blog_articles_shangyipian']);location.href='/u012582664/article/details/56845037';"><span><i class="fa fa-arrow-left"></i></span><em>安裝最新版python</em></a></div><div class="forward fr"><a href="javascript:void(0);" onclick="_gaq.push(['_trackEvent','function', 'onclick', 'blog_articles_xiayipian']);location.href='/u012582664/article/details/59120585';"><em>各種數據庫的注釋</em><span><i class="fa fa-arrow-right"></i></span></a></div>中的‘56845037’和‘59120585’，嘗試用正則：
pattern_l = r'''<a href="javascript:void(0);" onclick="_gaq.push(['_trackEvent','function', 'onclick', 'blog_articles_shangyipian']);location.href='(.+?)';">'''
re.findall(pattern_l,html)結果不成功。返回為空，有用：
soup = BeautifulSoup(html, "lxml")
print(soup.find_all(onclick="_gaq.push(['_trackEvent','function', 'onclick', 'blog_articles_shangyipian']);location.href='/u012582664/article/details/(.+?)';"))
還是返回空，請教各位怎么寫才行，是哪里出了問題
python 字符串匹配問題 >> python
這個答案描述的挺清楚的：
http://www.goodpm.net/postreply/python/1010000008985846/python字符串匹配問題.html