match “//” comments with regex but not inside a quote

Question

I need to match and replace some comments. for example:

$test = \"the url is http://www.google.com\";// comment \"<-- that quote needs to be matched
         


        

Answer 1

I have to admit, this regex took me a while to generate...but I'm pretty sure this will do what you are looking for:

Here's what's going on in the regex:

^ # start with the beginning of the line
(?:           # don't capture the following
 (
  ([^"'\/]*   # start the line with any character as long as it isn't a string or a comment
   (
    ("[^"]*") # grab a double quoted string
    |         # OR 
    ('[^']*') # grab a single quoted string
   )?         # but...we don't HAVE to match a string
   [\s]*      # allow for any amount of whitespace
  )?          # but...we don't HAVE to have any characters before the comment begins
  \/\/        # match the start of a comment
  [^"]*       # match any number of characters that isn't a double quote
 )            # end un-caught grouping
)             # end the non-capturing declaration
"             # match your commented double quote

The while loop in javascript is just find/replacing until it can't find any additional matches in a given line.