Question

我的字符串：

Russia's National Settlement Depository discusses why it believes the biggest blockchain opportunities have yet to be uncovered.<img alt="" height="1" src="http://feeds.feedburner.com/~r/CoinDesk/~4/rvoQUj-KDaw" width="1" />|One of the co-founder of digital currency startup Stellar announced their resignation today.<img alt="" height="1" src="http://feeds.feedburner.com/~r/CoinDesk/~4/xRzN7syt-v0" width="1" />|The editorial board for Bloomberg News has called for a permissive regulatory environment for blockchain development.<img alt="" height="1" src="http://feeds.feedburner.com/~r/CoinDesk/~4/ooQYB2iDxP8" width="1" />|

我想把这3个链接放到一个列表中：

http://feeds.feedburner.com/~r/CoinDesk/~4/rvoQUj-KDaw
http://feeds.feedburner.com/~r/CoinDesk/~4/xRzN7syt-v0
http://feeds.feedburner.com/~r/CoinDesk/~4/ooQYB2iDxP8

他们遵守这种模式：

src="http://feeds.feedburner.com/~r/CoinDesk/~4/rvoQUj-KDaw"

我知道我应该使用re.findall(pattern, string)来实现这一目标。

但最重要的问题是：如何构建适用于此处的模式？

我在编写正则表达式方面并不擅长......我总是感到困惑......几乎完成工作的是这一个：

pattern = 'http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\(\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+'

但我得到的只是这个清单：

[u'http://feeds.feedburner.com/', u'http://feeds.feedburner.com/', u'http://feeds.feedburner.com/']

看起来问题出在~r部分以及之后的事情上。

Answer 1

这些数据来自哪里？我建议使用html解析器而不是尝试使用正则表达式提取。如果来自html

，您可以从标签中提取完整值

下面我把你的字符串放在test.html中（对于python，使用beautifulsoup作为例子）

>>> from bs4 import BeautifulSoup
>>> soup = BeautifulSoup(open(r'A:\test.html'))
>>> [x['src'] for x in soup.findAll('img')]
['http://feeds.feedburner.com/~r/CoinDesk/~4/rvoQUj-KDaw', 'http://feeds.feedburner.com/~r/CoinDesk/~4/xRzN7syt-v0', 'http://feeds.feedburner.com/~r/CoinDesk/~4/ooQYB2iDxP8']

Answer 2

您遗漏了正则表达式中的~字符：

http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+~]|[!*,]|(?:%[0-9a-fA-F][0-9a-fA-F]))+

btw：this是在Python中测试正则表达式的超级方法！

Answer 3

试试这个脚本：

text1="""Russia's National Settlement Depository discusses why it believes the biggest blockchain opportunities have yet to be uncovered.<img alt="" height="1" src="http://feeds.feedburner.com/~r/CoinDesk/~4/rvoQUj-KDaw" width="1" />|One of the co-founder of digital currency startup Stellar announced their resignation today.<img alt="" height="1" src="http://feeds.feedburner.com/~r/CoinDesk/~4/xRzN7syt-v0" width="1" />|The editorial board for Bloomberg News has called for a permissive regulatory environment for blockchain development.<img alt="" height="1" src="http://feeds.feedburner.com/~r/CoinDesk/~4/ooQYB2iDxP8" width="1" />|"""
import re
print re.findall(r'(https?://\S+)', text1)

，结果是

['http://feeds.feedburner.com/~r/CoinDesk/~4/rvoQUj-KDaw"',   'http://feeds.feedburner.com/~r/CoinDesk/~4/xRzN7syt-v0"', 'http://feeds.feedburner.com/~r/CoinDesk/~4/ooQYB2iDxP8"']

Answer 4

试试这个：

(?:src=)(".*?")

并获得group \ 1

DEMO

如何使用正则表达式提取特定的img src url格式？

4 个答案: