BeautifulSoup get_text 返回 NoneType 对象

Question

我正在尝试使用 BeautifulSoup 进行网页抓取，我需要从此网页中提取标题，特别是“更多”标题部分。这是我迄今为止尝试使用的代码。

import requests
from bs4 import BeautifulSoup
from csv import writer

response = requests.get('https://www.cnbc.com/finance/?page=1')

soup = BeautifulSoup(response.text,'html.parser')

posts = soup.find_all(id='pipeline')

for post in posts:
    data = post.find_all('li')
    for entry in data:
        title = entry.find(class_='headline')
        print(title)

运行此代码以以下输出格式为我提供页面中的所有标题：

<div class="headline">
<a class=" " data-nodeid="105372063" href="/2018/08/02/after-apple-rallies-to-1-trillion-even-the-uber-bullish-crowd-on-wal.html">
           {{{*HEADLINE TEXT HERE*}}}
</a> </div>

但是，如果我在上面的代码中获取标题时使用 get_text() 方法，我只会得到前两个标题。

title = entry.find(class_='headline').get_text()

随后出现此错误：

Traceback (most recent call last):
  File "C:\Users\Tanay Roman\Documents\python projects\scrapper.py", line 16, in <module>
    title = entry.find(class_='headline').get_text()
AttributeError: 'NoneType' object has no attribute 'get_text'

为什么添加 get_text() 方法只返回部分结果。我该如何解决？

Answer 1

您误解了错误消息。不是.get_text()调用返回一个NoneType对象，而是类型的对象NoneType没有那个方法。

只有一个类型的对象NoneType，即值None。在这里它被返回，entry.find(class_='headline')因为它找不到entry与搜索条件匹配的元素。换句话说，对于该entry元素，没有具有 class 的子元素headline。

有两个这样的<li>元素，一个带有 id nativedvriver3，另一个带有nativedvriver9，并且两者都会出现该错误。您需要先检查是否有匹配的元素：

for entry in data:
    headline = entry.find(class_='headline')
    if headline is not None:
        title = headline.get_text()

如果您使用CSS 选择器，您会更轻松：

headlines = soup.select('#pipeline li .headline')
for headline in headlines:
    headline_text = headline.get_text(strip=True)
    print(headline_text)

这产生：

>>> headlines = soup.select('#pipeline li .headline')
>>> for headline in headlines:
...     headline_text = headline.get_text(strip=True)
...     print(headline_text)
...
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