删除字符串的特定部分

Question

Hi I have a file that contains several thousand file paths that I am looking to move to Wazhu. Problem is I need directories so what I have looks like >/apples/oranges/test.ex< What I need is >/apples/oranges< Not sure if Regex or just using str.replace() is better. As each line is different I would need to find the last / and remove it as well as everything up to <

Hopefully that makes sense.

Answer 1

Here's way using the split and join methods:

s = '>/apples/oranges/test.ex<'
s = '/'.join(s.split('/')[:-1])+'<' # Splits s by '/', remove the last object, join them together, plus a '<'
print(s)

Output:

>/apples/oranges<

Answer 2

You don't need regex to do this. You can simply use: os.path.split

import os
head, tail = os.path.split("/apples/oranges/test.ex")
print(head)
Output: /apples/oranges

I was stuck with the same issue, the above method solved it!

Answer 3

Try /[^/\r\n]*<$ replace this <

demo

Answer 4

you mean you want only everything except for the last "/"?

import os

file = open('file.txt', 'r')
for line in file.read().splitlines():
    print('/'.join(line.split('/',-1)[:-1]) + "<")

Answer 5

You could write

import re

s = '>/apples/oranges/test.ex<'

re.match(r'.*(?=\/)', s).group()

which returns

>/apples/oranges

This works because .* is greedy, so it consumes all forward slashes up to the last one. (?=\/) is a positive lookahead . group(0) also works.

Demo