如何在“br”之前提取文本?

时间:2015-12-08 15:20:36

标签: python html beautifulsoup html-parsing

我有一个小问题。我使用的是python 2.7.8。我正在尝试提取应该在< br >之前的文本。我喜欢:

<html>
<body>
<div class="entry-content" >
<p>Here is a listing of C interview questions on “Variable Names” along with answers, explanations and/or solutions:
</p>

<p>1. C99 standard guarantees uniqueness of ____ characters for internal names.<br>
a) 31<br>
b) 63<br>
c) 12<br>
d) 14</p>
<p> more </p>
<p>2. C99 standard guarantess uniqueness of _____ characters for external names.<br>
a) 31<br>
b) 6<br>
c) 12<br>
d) 14</p>
 </div>
</body>
</html>

我尝试过的代码目前正在&lt; br &gt;之后而不是br.这是代码:

from BeautifulSoup import BeautifulSoup, NavigableString, Tag
soup2 = BeautifulSoup(htmls)

for br2 in soup2.findAll('br'):
    next = br2.previousSibling
    if not (next and isinstance(next,NavigableString)):
        continue
    next2 = next.previousSibling
    if next2 and isinstance(next2,Tag) and next2.name == 'br':
        text = str(next).strip()
        if text:

            print "Found:", next.encode('utf-8')

输出给了我:

Found: 
a) 31
Found: 
b) 63
Found: 
c) 12
Found:
d) 14 
a) 31
Found: 
b) 6
Found: 
c) 12
Found:
d) 14 
Found:

知道我做错了什么。

1 个答案:

答案 0 :(得分:1)

首先,我会切换到BeautifulSoup version 4。 BeautifulSoup3很老了,不再维护了:

  

Beautiful Soup 3已被Beautiful Soup 4取代。

     

Beautiful Soup 3仅适用于Python 2.x,但也适用于Beautiful Soup 4   适用于Python 3.x.美丽的汤4更快,有更多的功能,   并与第三方解析器(如lxml和html5lib)配合使用。一旦   测试期结束,你应该使用Beautiful Soup 4为所有新的   项目

执行命令

pip install beautifulsoup4

并从以下位置更改您的导入声明:

from BeautifulSoup import BeautifulSoup

为:

from bs4 import BeautifulSoup

现在,我要做的是找到问题文本和get the following br siblings。对于每个兄弟姐妹,获取next_sibling这将是答案选项。工作代码:

soup = BeautifulSoup(data, "html5lib")  # using "html5lib" parser here

for question in soup.find_all(text=re.compile(r"^\d+\.")):
    answers = [br.next_sibling.strip() for br in question.find_next_siblings("br")]

    print(question)
    print(answers)
    print("------")

对于问题中提供的示例HTML,它会打印:

1. C99 standard guarantees uniqueness of ____ characters for internal names.
[u'a) 31', u'b) 63', u'c) 12', u'd) 14']
------
2. C99 standard guarantess uniqueness of _____ characters for external names.
[u'a) 31', u'b) 6', u'c) 12', u'd) 14']
------

请注意,您可能需要安装html5lib library

pip install html5lib