如果标签只有一个，Find (Beautiful Soup) 返回 None

Question

谁能帮助我理解这种现象？如果标签只有一个，'find' 将返回 None。 （我已经尝试过'lxml'，但没有帮助）。这是我在 IDE 中所做和接收的部分内容：

>>> driver = webdriver.Chrome("D:\\Text documents\\for work\\English project\\chromedriver")
>>> driver.get('https://www.interactive-english.ru/uprazhneniya/408-conditionals-exercise/')
>>> content = driver.page_source
>>> soup = BeautifulSoup(content, 'lxml')
>>> FullList = soup.findAll(['ol', 'h4', 'h5']);
>>> htmlF = FullList[1]

>>> htmlF

<ol>
    <li>
        Perhaps one day a cat will follow you home.<br />
        What would you do...
    </li>
    <li>
        Perhaps one day somebody will ask you to sing your favourite song.<br />
        What would you do...
    </li>
    <li>
        Perhaps one day you will find a hidden treasure.<br />
        What would you do...
    </li>
    <li>
        Perhaps one day somebody will throw an egg at you.<br />
        What would you do...
    </li>
    <li>
        Perhaps one day your car will be stolen.<br />
        What would you do...
    </li>
</ol>

>>> print(htmlF.find('li'))
<li>Perhaps one day a cat will follow you home.<br/>What would you do...</li>
>>> print(htmlF.find('ol'))
None
>>> 

Answer 1

什么时候做的

htmlF = FullList[1]

检索到的顶层是ol 标记。其中没有嵌套的ol，这就是为什么当你调用.find('ol')时你会得到None。

您可以通过以下方式检查：

print(htmlF.name)  
>> 'ol'

你可以的

htmlF.find('li') 

例如，要获得第一个孩子，因为 li 是您将 htmlF 设置为的父 ol 中的孩子。

Answer 2

试试：

soup = BeautifulSoup(content, 'html.parser')
FullList = soup.findAll(['ol', 'h4', 'h5']);
for fl in FullList:
    print(fl)

它会为我找到所有元素。