Regex match occurrences only after character sequence

问题

I want to find all the characters after w's that occur in this string, but only the ones after foo

edward woodward foo edward woodward

/(?<=w)./g gives me 6 matches

edward woodward foo edward woodward

I only want the 3 matches that occur after foo. How would I modify the regex to narrow the scope of the search?

回答1:

You may use the following regex with a PCRE engine:

(?:\bfoo\b|\G(?!^))[^w]*w\K.

See the regex demo.

Details

• (?:\bfoo\b|\G(?!^)) - either a whole word foo (\bfoo\b) or (|) the end of the previous match (\G(?!^))
• [^w]* - any 0+ chars other than w
• w - a w char
• \K - match reset operator discarding all text matched so far
• . - any char (other than line break chars, if you need to match them with . add (?s) at the pattern start or replace . with (?s:.))

来源：https://stackoverflow.com/questions/48875506/regex-match-occurrences-only-after-character-sequence