preg_replace在HTML attr结束之前添加一些东西

Question

Right now, I can use preg_replace to add something at the beginning of an HTML attribute this way:

$output = preg_replace('/class="/', 'class="$new_class, $output, 1);

How can I add something at the end of the HTML attribute?

Answer 1

You should change your regex to:

(class="[^"]*)

which means capturing a class=" and everything else up to a double quotation mark ". Then use \1 back-reference to first capturing group in replacement string for appending new class to it:

preg_replace('/(class="[^"]*)/', "$1 $new_class", $output);

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