我不知道以下是否可能.
我们假设我有以下文字：
我们假设我有以下文字：
<ul class="yes">
<li><img src="whatever1"></li>
<li><img src="whatever2"></li>
<li><img src="whatever3"></li>
<li><img src="whatever4"></li>
</ul>
<ul class="no">
<li><img src="whatever5"></li>
<li><img src="whatever6"></li>
<li><img src="whatever7"></li>
<li><img src="whatever8"></li>
</ul>
我想将ul中的每个img的src与class yes匹配.
我想要一个正则表达式回复我：
whatever1 whatever2 whatever3 whatever4
如何在一个正则表达式中加入这样的两个正则表达式？
<ul class="yes">(.+?)<\/ul> <img src="(whatever.+?)">
解决方法
众所周知,正则表达式难以用于解析类似XML的东西.更好地跳过这个想法并使用适当的HTML解析器滚动,例如,使用
BeautifulSoup4：
import bs4
html = """
<ul class="yes">
<li><img src="whatever1"></li>
<li><img src="whatever2"></li>
<li><img src="whatever3"></li>
<li><img src="whatever4"></li>
</ul>
<ul class="no">
<li><img src="whatever5"></li>
<li><img src="whatever6"></li>
<li><img src="whatever7"></li>
<li><img src="whatever8"></li>
</ul>
"""
soup = bs4.BeautifulSoup(html)
def match_imgs(tag):
return tag.name == 'img' \
and tag.parent.parent.name == 'ul' \
and tag.parent.parent['class'] == ['yes']
imgs = soup.find_all(match_imgs)
print(imgs)
whatevers = [i['src'] for i in imgs]
print(whatevers)
产量：
[<img src="whatever1"/>,<img src="whatever2"/>,<img src="whatever3"/>,<img src="whatever4"/>] [u'whatever1',u'whatever2',u'whatever3',u'whatever4']
