PHP Regex match multiple string combinations insinde a string and remove unwanted letters between all matches

Question

I have a string with several lines of CSS code. I want to match all occurences of :

background:url(" url ");

and remove everything except the filename.

Example input:

background:url("http://external_link.com/images/my_suspicious_file.png");
background:url("rubish.com/images/my_suspicious_file.jpg");
background:url("retarded_input/folder/flodder/my_suspicious_file.gif");

Expected output

background:url("my_suspicious_file.png");
background:url("my_suspicious_file.jpg");
background:url("my_suspicious_file.gif");

Answer 1

Search pattern:

background:url\(".*\/(.*?)"\);

Replace pattern:

background:url("$1");

You'll need to escape the strings above for PHP, and I'm assuming you are not using the s option (single line).

Update

With everything on the same line:

background:url\("[^"]*\/(.*?)"\);

Same replace pattern.