I want to be able to match the following texts
top of radio 54 / bottom 27
radio top 54 / bottom 27
The word top can be before or after radio only for the first half of the text (before /). top that appears after / should not be matched.
I tried to use the following pattern that encloses the lookahead for the first half with parentheses.
((?=top).*radio\s\d{2}\s)\/\D*bottom\s\d{2}
But it doesn't work like I expected. Only matches first string, but not second.
You may use this regex with a lookahead:
^(?=[^/]*\btop\s)[^/]*radio[^/]+\d{2}\s+/\D*bottom\s+\d{2}$
RegEx Breakup:
^: Start(?=[^/]*\btop\s): Lookahead to assert presence of word top being present before matching a /. This is to ensure we match word top before / only[^/]*: Match 0 more of any char that is not a /radio: Match radio[^/]+: Match 1+ of any char that is not a /\d{2}: Match 2 digits\s+: Match 1+ whitespaces/: Match a /\D*: Match 0 or more non-digitsbottom: Match bottom\s+: Match 1+ whitespace\d{2}: Match 2 digits$: End