python：在一个字符后分割字符串

Question

I have a string with two "-"

467.2-123-hdxdlfow

I want to remove everything after the second "-" so that I get "467.2-123". What is the best way to do this?

Answer 1

before, sep, after = theString.rpartition("-")

这会将str分成最后一次出现的“ - ”，你的答案就是before的变量。

Answer 2

In [6]: "-".join('467.2-123-hdxdlfow'.split('-')[0:2])
Out[6]: '467.2-123'

Answer 3

 >>> s = '467.2-123-hdxdlfow'
 >>> s[:s.rfind('-')]
 '467.2-123'

Answer 4

If you are after everything but the last element, I have modifed spicavigo's answer to exclude the last element.

a='467.2-123-hdxdlfow'
'-'.join(a.split('-')[:-1])

Answer 5

a='467.2-123-hdxdlfow'
'-'.join(a.split('-')[:2])

If you have exactly 2 '-', you could do

a.rsplit('-',1)[0]

Answer 6

Try this regex

([^-]*-[^-]*)-.*

and ask the result for the first capturing group ( (...) in the example).

Answer 7

你可以尝试这个result = re.sub("([^-]*-[^-]*)(-.*$)", r"\\1", '467.2-123-hdxdlfow')给出467.2-123