使用Python的正则表达式

Question

我正在尝试捕获从特定URL，特定值下载但没有成功的模式。 模式的一部分是：

"<a href="/wiki/All_My_Loving" title="All My Loving">All My Loving</a>"</td>\n<td style="text-align:center;">1963</td>\n<td><i>UK: <a href="/wiki/With_the_Beatles" title="With the Beatles">With the Beatles</a><br />\nUS: <a href="/wiki/Meet_The_Beatles!" class="mw-redirect" title="Meet The Beatles!">Meet The Beatles!</a></i></td>\n<td>McCartney</td>\n<td>McCartney</td>\n<td style="text-align:center;">\xe2\x80\x94</td>\n<td style="text-align:center;"><span style="display:none" class="sortkey">7001450000000000000\xe2\x99\xa0</span>45</td>\n<td></td>\n</tr>\n<tr>\n<td>"<a href="/wiki/All_Things_Must_Pass_(song)" title="All Things Must Pass (song)">All Things Must Pass</a>"</td>\n<td style="text-align:center;">1969</td>\n<td><i><a href="/wiki/Anthology_3" title="Anthology 3">Anthology 3</a></i></td>\n<td>Harrison</td>\n<td>Harrison</td>\n<td style="text-align:center;">\xe2\x80\x94</td>\n<td style="text-align:center;">\xe2\x80\x94</td>\n<td></td>\n</tr>\n<tr>\n<td>"<a href="/wiki/All_Together_Now_(The_Beatles_song)" class="mw-redirect" title="All Together Now (The Beatles song)">All Together Now</a>"</td>\n<td style="text-align:center;">1967</td>\n<td><i><a href="/wiki/Yellow_Submarine_(album)" title="Yellow Submarine (album)">Yellow Submarine</a></i></td>\n<td>McCartney, with Lennon</td>\n<td>McCartney, with Lennon</td>\n<td style="text-align:center;">\xe2\x80\x94</td>\n<td style="text-align:center;">\xe2\x80\x94</td>\n<td></td>\n</tr>\n<tr>\n<td>"

我想用文件中的特定值捕获Title和第一个<td>McCartney</td>并将其打印为JSON文件。

我可以在正则表达式的FOR循环中运行吗？ 我如何使用python做到这一点？

谢谢，

Answer 1

如果要解析HTML，请使用HTML解析器（例如BeautifulSoup ），而不要使用正则表达式。

from bs4 import BeautifulSoup

html = '''<a href="/wiki/All_My_Loving" title="All My Loving">All My Loving</a>"</td>\n<td style="text-align:center;">1963</td>\n<td><i>UK: <a href="/wiki/With_the_Beatles" title="With the Beatles">With the Beatles</a><br />\nUS: <a href="/wiki/Meet_The_Beatles!" class="mw-redirect" title="Meet The Beatles!">Meet The Beatles!</a></i></td>\n<td>McCartney</td>\n<td>McCartney</td>\n<td style="text-align:center;">\xe2\x80\x94</td>\n<td style="text-align:center;"><span style="display:none" class="sortkey">7001450000000000000\xe2\x99\xa0</span>45</td>\n<td></td>\n</tr>\n<tr>\n<td>"<a href="/wiki/All_Things_Must_Pass_(song)" title="All Things Must Pass (song)">All Things Must Pass</a>"</td>\n<td style="text-align:center;">1969</td>\n<td><i><a href="/wiki/Anthology_3" title="Anthology 3">Anthology 3</a></i></td>\n<td>Harrison</td>\n<td>Harrison</td>\n<td style="text-align:center;">\xe2\x80\x94</td>\n<td style="text-align:center;">\xe2\x80\x94</td>\n<td></td>\n</tr>\n<tr>\n<td>"<a href="/wiki/All_Together_Now_(The_Beatles_song)" class="mw-redirect" title="All Together Now (The Beatles song)">All Together Now</a>"</td>\n<td style="text-align:center;">1967</td>\n<td><i><a href="/wiki/Yellow_Submarine_(album)" title="Yellow Submarine (album)">Yellow Submarine</a></i></td>\n<td>McCartney, with Lennon</td>\n<td>McCartney, with Lennon</td>\n<td style="text-align:center;">\xe2\x80\x94</td>\n<td style="text-align:center;">\xe2\x80\x94</td>\n<td></td>\n</tr>\n<tr>\n<td>
'''

soup = BeautifulSoup(html, 'html.parser')
a = soup.find('a')  # will only find the first <a> tag
print(a.attrs['title'])

tds = soup.find_all('td')  # will find all <td> tags
for td in tds:
    if 'McCartney' in td.text:
        print(td)

#  All My Loving
#  <td>McCartney</td>
#  <td>McCartney</td>
#  <td>McCartney, with Lennon</td>
#  <td>McCartney, with Lennon</td>