BeautifulSoup-通过标签内的文本搜索
观察以下问题:
import re
from bs4 import BeautifulSoup as BS
soup = BS("""
<a href="/customer-menu/1/accounts/1/update">
Edit
</a>
""")
# This returns the <a> element
soup.find(
'a',
href="/customer-menu/1/accounts/1/update",
text=re.compile(".*Edit.*")
)
soup = BS("""
<a href="/customer-menu/1/accounts/1/update">
<i class="fa fa-edit"></i> Edit
</a>
""")
# This returns None
soup.find(
'a',
href="/customer-menu/1/accounts/1/update",
text=re.compile(".*Edit.*")
)
由于某种原因,当<i>
标签也存在时,BeautifulSoup将不匹配文本。找到标签并显示其文字会产生
>>> a2 = soup.find(
'a',
href="/customer-menu/1/accounts/1/update"
)
>>> print(repr(a2.text))
'\n Edit\n'
对。根据文档,汤使用正则表达式的匹配功能,而不是搜索功能。所以我需要提供DOTALL标志:
pattern = re.compile('.*Edit.*')
pattern.match('\n Edit\n') # Returns None
pattern = re.compile('.*Edit.*', flags=re.DOTALL)
pattern.match('\n Edit\n') # Returns MatchObject
好的。看起来不错。让我们一起喝汤
soup = BS("""
<a href="/customer-menu/1/accounts/1/update">
<i class="fa fa-edit"></i> Edit
</a>
""")
soup.find(
'a',
href="/customer-menu/1/accounts/1/update",
text=re.compile(".*Edit.*", flags=re.DOTALL)
) # Still return None... Why?!
编辑
我基于geckons的解决方案答案:我实现了以下帮助器:
import re
MATCH_ALL = r'.*'
def like(string):
"""
Return a compiled regular expression that matches the given
string with any prefix and postfix, e.g. if string = "hello",
the returned regex matches r".*hello.*"
"""
string_ = string
if not isinstance(string_, str):
string_ = str(string_)
regex = MATCH_ALL + re.escape(string_) + MATCH_ALL
return re.compile(regex, flags=re.DOTALL)
def find_by_text(soup, text, tag, **kwargs):
"""
Find the tag in soup that matches all provided kwargs, and contains the
text.
If no match is found, return None.
If more than one match is found, raise ValueError.
"""
elements = soup.find_all(tag, **kwargs)
matches = []
for element in elements:
if element.find(text=like(text)):
matches.append(element)
if len(matches) > 1:
raise ValueError("Too many matches:\n" + "\n".join(matches))
elif len(matches) == 0:
return None
else:
return matches[0]
现在,当我想找到上面的元素时,我就运行 find_by_text(soup, 'Edit', 'a', href='/customer-
menu/1/accounts/1/update')