如何在Python中删除以某些字符开头和结尾的子字符串

Question

I have a string like this

foldername/pic.jpg

How can I remove this part /pic so the new string will become foldername.jpg ?

EDIT: I want to replace any string that starts with / and end with . with a dot (.) so the new file name only contains the foldername.jpg

Answer 1

You can use re module. Try -

import re
a = 'foldername/pic.jpg'
out = re.sub(r'/.*\.', r'.', a)
print(out)

Answer 2

if that is all you have, you can do it like this:

name = 'foldername/pic.jpg'
root = name.split('/')[0]
ext = name.split('.')[1]
name = root + ext

but if you are splitting file-paths, you will be better off with os.path commands, for example:

import os
name = 'foldername/pic.jpg'
root = os.path.dirname(name)
_, ext = os.path.splitext(name)
name = root + '.' + ext

both cases return a string foldername.jpg in these cases, but the os.path commands are more flexible

Answer 3

For a more generic solution, try regular expressions. In your specific example, I will make the assumption you want to remove a substring that starts with '/', and ends with 'c' (ie, /pic).

In [394]: import re
In [395]: re.sub(r'(.+)\/\w+c(.+)', r'\1\2', 'foldername/pic.jpg')
Out[395]: 'foldername.jpg'

Just note that the second argument needs the raw string encapsulator r' ', if you want to interpolate variables, else the \\1 or \\2 have no effect.