python - 将匹配的子字符串从列表中提取到 Python 中的新列表

Question

我有一个如下所示的文本文件:

garbage
moregarbaged89849843
MDeduri09ri44830
Some short sentence
Whatever ... key: d11001bfa937eee2f84f55a11b207356 (KID=01002d737832455680cffbadf1092baf)
Whatever2 ... key: a0ee2d0f8272355f750c5434db85291a (KID=0101bfa0ab9641a0b863ef76519a48d3)
Whatever3 ... key: fe216ba17e5af807ce5af8e43cf3c031 (KID=0102900a2bc54111833631ea7bb855ed)
77EB0A2C7C42EDC27A3D26E72A02BB29:01002d737832455680cffbadf1092baf status 'garbage'
blah blah:0101bfa0ab9641a0b863ef76519a48d3 has status 'usable'
77EB0A2C7C42EDC27A3D26E72A02BB29:blah blah

我只关心 key 和 KID 部分，想把它们提取到单独的列表中

我的正则表达式分别是 key: (\w|\d){30,} 和 KID=(\w|\d){30,} .

我使用的代码是

matchkid = re.compile('KID=(\w|\d){30,}')
matchkey = re.compile('key: (\w|\d){30,}')

filteredkids = [a for a in lis if matchkid.search(a)]
filteredkeys = [b for b in lis if matchkey.search(b)]

print(filteredkids)
print('\n')
print(filteredkeys)

其中 lis 是由文本文档的行组成的列表

输出是

['Whatever ... key: d11001bfa937eee2f84f55a11b207356 (KID=01002d737832455680cffbadf1092baf)', 'Whatever2 ... key: a0ee2d0f8272355f750c5434db85291a (KID=0101bfa0ab9641a0b863ef76519a48d3)', 'Whatever3 ... key: fe216ba17e5af807ce5af8e43cf3c031 (KID=0102900a2bc54111833631ea7bb855ed)']


['Whatever ... key: d11001bfa937eee2f84f55a11b207356 (KID=01002d737832455680cffbadf1092baf)', 'Whatever2 ... key: a0ee2d0f8272355f750c5434db85291a (KID=0101bfa0ab9641a0b863ef76519a48d3)', 'Whatever3 ... key: fe216ba17e5af807ce5af8e43cf3c031 (KID=0102900a2bc54111833631ea7bb855ed)']

这是错误的，期望的输出是

['KID=01002d737832455680cffbadf1092baf', 'KID=0101bfa0ab9641a0b863ef76519a48d3', 'KID=0102900a2bc54111833631ea7bb855ed']

['key: d11001bfa937eee2f84f55a11b207356', 'key: a0ee2d0f8272355f750c5434db85291a', 'key: fe216ba17e5af807ce5af8e43cf3c031']

我尝试调整我的正则表达式并查看其他类似问题，但似乎没有任何效果，而且大多数时候我只是得到空列表。

希望能在这里找到一些指导，提前致谢

Answer 1

(\w|\d){30,} 不是一个好的模式，因为它创建了一个重复的捕获组，并且它本身是多余的:\w 匹配数字，所以 \w{30,} 就足够了。

接下来，您将使用仅返回 Match 数据对象的 re.search，并使用 listeneing comprehension 迭代该对象，同时您需要从字符串中获取所有匹配项。

您可以通过使用修复代码

filteredkids = re.findall(r'KID=\w{30,}', text)
filteredkeys = re.findall(r'key: \w{30,}', text)

参见 Python demo :

import re
text = """garbage
moregarbaged89849843
MDeduri09ri44830
Some short sentence
Whatever ... key: d11001bfa937eee2f84f55a11b207356 (KID=01002d737832455680cffbadf1092baf)
Whatever2 ... key: a0ee2d0f8272355f750c5434db85291a (KID=0101bfa0ab9641a0b863ef76519a48d3)
Whatever3 ... key: fe216ba17e5af807ce5af8e43cf3c031 (KID=0102900a2bc54111833631ea7bb855ed)
77EB0A2C7C42EDC27A3D26E72A02BB29:01002d737832455680cffbadf1092baf status 'garbage'
blah blah:0101bfa0ab9641a0b863ef76519a48d3 has status 'usable'
77EB0A2C7C42EDC27A3D26E72A02BB29:blah blah"""
filteredkids = re.findall(r'KID=\w{30,}', text)
filteredkeys = re.findall(r'key: \w{30,}', text)
print( filteredkids )
print( filteredkeys )

输出:

['KID=01002d737832455680cffbadf1092baf', 'KID=0101bfa0ab9641a0b863ef76519a48d3', 'KID=0102900a2bc54111833631ea7bb855ed']
['key: d11001bfa937eee2f84f55a11b207356', 'key: a0ee2d0f8272355f750c5434db85291a', 'key: fe216ba17e5af807ce5af8e43cf3c031']