Question

I know people often get told off here for using regexes to fiddle with HTML which I understand but I think in this case I have a valid use for it to alter a CSS file. Unfortunately I am hopeless at writing them myself.

I’m writing a script (PHP) that needs to dynamically add/remove items in a CSS file. As an example the CSS file may have the following declaration:

.cat-item-4 {
    background: #ff0fcd;
}

Presumably a regex is possible to remove this whole declaration? It may contain other things asides from “background” so would need to spot the .cat-item-4 class and then remove both that and everything between and including the parentheses. The whole lot basically.

Any help appreciated.

Answer 1

You can use a regex find/replace with:

$re = "#\.\bcat-item-4\b.+?\}#s";

Coupled with the modifier PCRE_DOTALL (s), this will find all classes with the name bcat-item-4. The # signs tell PHP what delimiter to use, because after the second #, the ‘s’ indicates that the . should match newlines, which is essential in removing the entire declaration.