Question

Given this file中提取所有href和标题：

<a data-parent="#accordion1" data-toggle="collapse" href="# fruitName1" title="Click to expand drug name">
<span class="list-unstyled" style="text-decoration: none;"></span> GLIPIZIDE 
         </a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114223" title="Click to view LEMONS (LEMONS) | POQ  #114223 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 1 ">
                              LEMONS (LEMONS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114226" title="Click to view LEMONS (LEMONS) | POQ  #114226 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 2 ">
                              LEMONS (LEMONS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114305" title="Click to view LEMONS (LEMONS) | POQ  #114305 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 3 ">
                              LEMONS (LEMONS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114370" title="Click to view LEMONS (LEMONS) | POQ  #114370 | BOX;67 PZ | Discontinued | FRUIT COMPANY 1 ">
                              LEMONS (LEMONS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114378" title="Click to view LEMONS (LEMONS) | POQ  #114378 | BOX;67 PZ | Discontinued | FRUIT COMPANY 4 ">
                              LEMONS (LEMONS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114387" title="Click to view LEMONS (LEMONS) | POQ  #114387 | BOX;67 PZ | Discontinued | FRUIT COMPANY 5 ">
                              LEMONS (LEMONS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114438" title="Click to view LEMONS (LEMONS) | POQ  #114438 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 2 ">
                              LEMONS (LEMONS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114497" title="Click to view LEMONS (LEMONS) | POQ  #114497 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 5 ">
                              LEMONS (LEMONS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114542" title="Click to view LEMONS (LEMONS) | POQ  #114542 | BOX;67 PZ | Discontinued | FRUIT COMPANY 3 ">
                              LEMONS (LEMONS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114550" title="Click to view LEMONS (LEMONS) | POQ  #114550 | 
         </a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=117270" title="Click to view GRAPES (GREEN GRAPES ; AUS) | POQ  #117270 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 10  ">
                              GRAPES (GREEN GRAPES ; AUS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=117511" title="Click to view GRAPES (GREEN GRAPES ; AUS) | POQ  #117511 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 11 ">
                              GRAPES (GREEN GRAPES ; AUS)</a>
<a href="/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=117620" title="Click to view GRAPES (GREEN GRAPES ; AUS) | POQ  #117620 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 12 ">

使用正则表达式或漂亮的汤，如何提取所有<a href="" title="">，在www.example.com标记之前添加href：

www.example.com/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114223 |  title= | Click to view LEMONS (LEMONS) | POQ  #114223 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 1 | LEMONS (LEMONS)
www.example.com/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114226 |  title= | Click to view LEMONS (LEMONS) | POQ  #114226 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 2 | LEMONS (LEMONS)
www.example.com/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114305 |  title= | Click to view LEMONS (LEMONS) | POQ  #114305 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 3 | LEMONS (LEMONS)
www.example.com/loads/data/usersindex.cfm?event=overview.subprocess&amp;ApplNo=114370 |  title= | Click to view LEMONS (LEMONS) | POQ  #114370 | BOX;67 PZ | Discontinued | FRUIT COMPANY 1 | LEMONS (LEMONS)

我试图：

for a in soup.tbody.findAll('a', href=True):
    r = re.compile('(?<=href=").*?(?=")')
    r.findall(str(a)

和

for a in soup.tbody.findAll('a', href=True):
    print (a.find('a')['href'])
    print (a.find('a')['title'])

但是，我不知道如何重新排列标题和href。的更新

根据odradek的回答，我尝试了这个：

soup = BeautifulSoup(open('file.htm'), 'lxml')
for a in soup.tbody.findAll('a', href=True):
    html = a
    PREFIX = 'www.example.com'
    template = '{prefix}{url} | {title}'.format
    links = [template(prefix=PREFIX, url=e['href'], title=e['title']) for e in html.find_all('a', href=True)]
    print(links)

但是我得到了：

[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]

Answer 1

你可以使用BeautifulSoup解析方法而不是复杂的正则表达式：

# this is the url you want to add at the beginning
PREFIX = 'www.example.com'

# the template of your desired output
template = '{prefix}{url} | {title}'.format

# the resulting list, please note that "html" variable is
# the given source code.
links = [template(prefix=PREFIX, url=e.get('href'), title=e.get('title'))
         for e in html.find_all('a', href=True)]

针对列表中的两个a标记运行时：

$ python get_all_a.py
www.example.com/loads/data/usersindex.cfm?event=overview.subprocess&ApplNo=117511 | Click to view GRAPES (GREEN GRAPES ; AUS) | POQ  #117511 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 11 
www.example.com/loads/data/usersindex.cfm?event=overview.subprocess&ApplNo=117620 | Click to view GRAPES (GREEN GRAPES ; AUS) | POQ  #117620 | BOX;67 PZ | PRESENTATION | FRUIT COMPANY 12

根据您的更新，您不应该将这段代码放在for循环中，而是：

html = BeautifulSoup(open('file.htm'), 'html.parser')

PREFIX = 'www.example.com'

template = '{prefix}{url} | {title}'.format

# inside this list comprehension is your for loop implied
links = [template(prefix=PREFIX, url=e.get('href'), title=e.get('title'))
         for e in html.find_all('a', href=True)]

Answer 2

这不是regexp的任务。您可以使用在odradek的答案中提供的BeautifulSoup，或者有我最喜欢的替代lxml，在我看来，这会产生更易读的代码：

from lxml import etree

tree = etree.fromstring(html)
for element in tree.xpath('//a'):
    print('www.example.com' + element.get('href'))
    print('title: ' + element.get('title'))

如何从几个“<a href="" title=""> tags?

2 个答案: