Remove CSS inside comments using PHP

Question

Let's say I have a string like this:

$css = '.class {
    color: red;
}

/* Start Comment */
.replace {
    content: "me";
}
/* End Comment */';

How can I remove everything inside the comment, including the comment itself?

I want this result:

.class {
    color: red;
}

I've tried something like this, but it doesn't do it:

$css = preg_replace( '#(/* Start Comment */).*?(/* End Comment */)#', '', $css );

Am I missing something ridiculously obvious here?

Really appreciate any feedback - regex is something I need to study further.

`*` is a special character, you have to escape it if you want to match a literal `*`. `.` doesn't match the newline character `\n` by default. To allow it to match the newline character too, you have to use the `s` modifier. — Casimir et Hippolyte, Oct 16 '17 at 22:19

score 1 · Accepted Answer · answered Oct 16 '17 at 22:23

1

$css = preg_replace( '#(/\\* Start Comment \\*/).*?(/\\* End Comment \\*/)#s', '', $css );

Additionally, the * should be escaped to get the desired effect. The / are fine as you are using another delimiter.

answered Oct 16 '17 at 22:23

clemens321

/\/\*.+;/s also matches your string – miknik Oct 16 '17 at 22:29
You don't have to use two backslashes to escape the `*` only one suffice. Note that you can also use the `\Q...\E` feature for long literal parts. – Casimir et Hippolyte Oct 16 '17 at 22:35
It works without but it is cleaner to always escape the backslash, even in single quotes. Besides single quotes itself the only thing to manually escape. – clemens321 Oct 16 '17 at 22:40

1 Answers1