正则表达式：一个字符的最后一次出现和另一个字符的第一次出现之间的匹配

Question

I have the following string:

COUNTRY/CITY/street_number_floor_tel

I'd like to extract what is after the last occurrence of '/' and first occurrence of '_'. So the result is:

street

So far I've managed to come up with this regex:

[^/]+(?=_)

which results in the following:

street_number_floor

So I basically don't know how to stop after finding the first occurrence of '_'.

Many thanks for any hints in advance!

Answer 1

You may use

(?<=/)[^/_]+(?=_[^/]*$)

See the regex demo

Details

• (?<=/) - a positive lookbehind requiring a / immediately before the match
• [^/_]+ - 1+ chars other than / and _
• (?=_[^/]*$) - a positive lookahead that requires _ , then 0+ chars other than / till the end of string immediately to the right of the current location.