Regex to remove multi line comments

Question

I am trying to use this regex (JS):

/\\/\\*(.*)\\*\\//g

To replace

/*
sdandsads
*/

with nothing.

Answer 1

Two problems:

1. In javascript, there's no dotall modifier. You'll have to use a hack to allow matching newlines, such as using [^].
2. You're using greedy matching. If there are multiple comments in your input, everything between them will be eaten.

Solution:

/\/\*[^]*?\*\//g

Example:

> '/*abc\ncde*/qqq/*iop\n\njj*/'.replace(/\/\*[^]*?\*\//g, '')
qqq

Answer 2

the dot catches everything except newlines..( if the dotall is false )

so either use the dotall ( as mentioned in other answers/comments this is not supported in javascript, but i will leave it here for reference )

/\/\*(.*)\*\//gs

or add the whitespace chars \s in your expressions

/\/\*((\s|.)*?)\*\//g

Alan mentioned in his comment a bad performance from the answer i gave so use the following instead.. ( which translates to everything whitespace and everything non whitespace, so everything.. )

/\/\*([\s\S]*?)\*\//g