Question

我正在尝试BeautifulSoup进行网页抓取，并且需要从此webpage中提取标题，尤其是从“更多”标题部分中。这是我到目前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，将以以下输出格式显示页面中的所有标题：

<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，如果在上面的代码中获取标题时使用get_text（）方法，则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（）方法仅返回部分结果。而我该如何解决呢？

Answer 1

您误解了错误消息。并不是.get_text()调用返回一个NoneType对象，而是NoneType类型的对象没有该方法。

只有一个类型NoneType的对象，值None。在这里它是由entry.find(class_='headline')返回的，因为它无法在entry中找到与搜索条件匹配的元素。换句话说，对于该entry元素，没有类别为headline的子元素。

有两个这样的<li>元素，一个元素的ID为nativedvriver3，另一个元素的元素为nativedvriver9，这两个元素都将导致该错误。您需要先检查是否存在匹配的元素：

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

如果您使用CSS selector，则可以轻松得多：

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

这将产生：

>>> headlines = soup.select('#pipeline li .headline')
>>> for headline in headlines:
...     headline_text = headline.get_text(strip=True)
...     print(headline_text)
...
Hedge funds fight back against tech in the war for talent
Goldman Sachs sees more price pain ahead for bitcoin
Dish Network shares rise 15% after subscriber losses are less than expected
Bitcoin whale makes ‘enormous’ losing bet, so now other traders have to foot the bill
The 'Netflix of fitness' looks to become a publicly traded stock as soon as next year
Amazon slammed for ‘insult’ tax bill in the UK despite record profits
Nasdaq could plunge 15 percent or more as ‘rolling bear market’ grips stocks: Morgan Stanley
Take-Two shares surge 9% after gamemaker beats expectations due to 'Grand Theft Auto Online'
UK bank RBS announces first dividend in 10 years
Michael Cohen reportedly secured a $10 million deal with Trump donor to advance a nuclear project
After-hours buzz: GPRO, AIG & more
Bitcoin is still too 'unstable' to become mainstream money, UBS says
Apple just hit a trillion but its stock performance has been dwarfed by the other tech giants
The first company to ever reach $1 trillion in market value was in China and got crushed
Apple at a trillion-dollar valuation isn’t crazy like the dot-com bubble
After Apple rallies to $1 trillion, even the uber bullish crowd on Wall Street believes it may need to cool off

BeautifulSoup get_text返回NoneType对象

1 个答案: