Regex to get a specific part of an URL

Question

Say I've got an URL:

http://www.example.com/foo/bar/yes_no_no.html

I'm looking for a regex that can extract all the characters of the filename up to the first underscore. So in the above URL I want to extract "yes".

So far I managed to get the whole "yes_no_no" bit using:

/([^\\/]+)(?=\\.\\w+$)/ , but I can't seem to get it to only match "yes".

Answer 1

Try this:

/\/([^_\/]+)_?[^\/]*\.[a-z]+$/

Example:

 console.log('http://www.example.com/foo/bar/yes_no_no.html'.match(/\\/([^_\\/]+)_?[^\\/]*\\.[az]+$/)[1]) console.log('http://www.example.com/foo/bar/yes.html'.match(/\\/([^_\\/]+)_?[^\\/]*\\.[az]+$/)[1])