美丽的汤：寻找嵌套模式？

Question

soup.find_all will search a BeautifulSoup document for all occurrences of a single tag. Is there a way to search for particular patterns of nested tags?

For example, I would like to search for all occurrences of this pattern:

<div class="separator">
  <a>
    <img />
  </a>
</div>

Answer 1

Check out this part of the docs . You probably want a function like this:

def nested_img(div):
    child = div.contents[0]
    return child.name == "a" and child.contents[0].name == "img"

soup.find_all("div", nested_img)

PS: This is untested.

Answer 2

There are multiple ways to find the pattern, but the easiest one would be to use a CSS selector :

for img in soup.select('div.separator > a > img'):
    print img  # or img.parent.parent to get the "div"

Demo:

>>> from bs4 import BeautifulSoup
>>> data = """
... <div>
...     <div class="separator">
...       <a>
...         <img src="test1"/>
...       </a>
...     </div>
... 
...     <div class="separator">
...       <a>
...         <img src="test2"/>
...       </a>
...     </div>
... 
...     <div>test3</div>
... 
...     <div>
...         <a>test4</a>
...     </div>
... </div>
... """
>>> soup = BeautifulSoup(data)
>>> 
>>> for img in soup.select('div.separator > a > img'):
...     print img.get('src')
... 
test1
test2

I do understand that, strictly speaking, the solution would not work if the div has more than just one a child, or inside the a tag there is smth else except the img tag. If this is the case the solution can be improved with additional checks (will edit the answer if needed).