Question

I need a regular expression that will find a number(s) that is not inside parenthesis.
Example abcd 1 (35) (df)

It would only see the 1.

Is this very complex? I’ve tried and had no luck.
Thanks for any help

Answer 1

This is quite hard but something like this will probably do:

^(?:\()(\d+)(?:[^)])|(?:[^(0-9]|^)(\d+)(?:[^)0-9]|^)|(?:[^(])(\d+)(?:\))$

The problem is to match (123, 123) and also to not match the string 123 as the number 2 between the non-parentheses characters 1 and 3. Also there are probably some edge cases for start of and end of string.

My suggestion is to not use a regex for this. Maybe a regex that matches numbers and then use the capture info to check if the surrounding characters are not parentheses.