Searching on class tags with multiple spaces and w

问题:

I am trying to use BeautifulSoup to find all div containers with the class attribute beginning by "foo bar". I had hoped the following would work:

from bs4 import BeautifulSoup

import re

soup.findAll('div',class_=re.compile('^foo bar'))

However, it seems that the class definition is separated into a list, like ['foo','bar'], such that regular expressions are not able to accomplish my task. Is there a way I can accomplish this task? (I have reviewed a number of other posts, but have not found a working solution)

回答1:

You can use a syntax with a function that needs to return True or False, a lambda can do the trick too:

from bs4 import BeautifulSoup as soup
html = '''
<div class="foo bar bing"></div>
<div class="foo bang"></div>
<div class="foo bar1 bang"></div>
'''
soup = soup(html, 'lxml')
res = soup.find_all('div', class_=lambda s:s.startswith('foo bar '))
print(res)
>>> [<div class="foo bar bing"></div>]

---

res = soup.find_all('div', class_=lambda s:s.startswith('foo bar')) # without space
print(res)
>>> [<div class="foo bar bing"></div>, <div class="foo bar1 bang"></div>]

---

Another possible syntax with a function :

def is_a_match(clas):
    return clas.startswith('foo bar')

res = soup.find_all('div', class_=is_a_match)

Maybe this answer can help you too : https://stackoverflow.com/a/46719313/6655211