错误而使用Python 3

Question

从网页中提取链接

让我们考虑以下几点：

<div class="more reviewdata"> 

<a onclick="bindreviewcontent('1660651',this,false,'I found this review of Star Health Insurance pretty useful',925075287,'.jpg','I found this review of Star Health Insurance pretty useful %23WriteShareWin','http://www.mouthshut.com/review/Star-Health-Insurance-review-toqnmqrlrrm','Star Health Insurance',' 2/5');" style="cursor:pointer">Read More</a> 

</div> 

从类似上述情况，我想单独提取http链接如下：

http://www.mouthshut.com/review/Star-Health-Insurance-review-toqnmqrlrrm

为了达到这个目的，我使用BeautifulSoup和Python中的正则表达式编写了一个代码。代码如下：

import urllib.request 
import re 

from bs4 import BeautifulSoup 
page = urllib.request.urlopen('http://www.mouthshut.com/product-reviews/Star-Health-Insurance-reviews-925075287').read() 

soup = BeautifulSoup(page, "html.parser") 

required = soup.find_all("div", {"class": "more reviewdata"}) 

for link in re.findall('http://www.mouthshut.com/review/Star-Health-Insurance-review-[a-z]*', required): 
    print(link) 

在执行时，如下程序抛出一个错误：

Traceback (most recent call last): 

File "E:/beautifulSoup20April2.py", line 11, in <module> 

for link in re.findall('http://www.mouthshut.com/review/Star-Health-Insurance-review-[a-z]*', required): 

File "C:\Program Files (x86)\Python35-32\lib\re.py", line 213, in findall 
return _compile(pattern, flags).findall(string) 

TypeError: expected string or bytes-like object 

有人建议应该做什么单独提取URL没有任何错误？

Answer 1

首先，你需要循环required，第二你要的对象<class 'bs4.element.Tag'>上使用regex（蟒蛇在抱怨这一点），那么你就需要从bs4元素，它可以与prettify()进行提取html

这里有一个工作版本：

import urllib.request 
import re 
from bs4 import BeautifulSoup 
page = urllib.request.urlopen('http://www.mouthshut.com/product-reviews/Star-Health-Insurance-reviews-925075287').read() 
soup = BeautifulSoup(page, "html.parser") 
required = soup.find_all("div", {"class": "more reviewdata"}) 
for div in required: 
    for link in re.findall(r'http://www\.mouthshut\.com/review/Star-Health-Insurance-review-[a-z]*', div.prettify()): 
     print(link) 

---

输出：

http://www.mouthshut.com/review/Star-Health-Insurance-review-ommmnmpmqtm 
http://www.mouthshut.com/review/Star-Health-Insurance-review-rmqulrolqtm 
http://www.mouthshut.com/review/Star-Health-Insurance-review-ooqrupoootm 
http://www.mouthshut.com/review/Star-Health-Insurance-review-rlrnnuslotm 
http://www.mouthshut.com/review/Star-Health-Insurance-review-umqsquttntm 
...