PHP DomDocument alter conditional comments

Question

I have this html file with a conditional comment.

Answer 1

foreach($dom->getElementsByTagName('head') as $head) {
    foreach($head->childNodes as $node) {
        if($node instanceof DOMComment) {
            $node->replaceData(16,60,'test');
        }
    }
}

This code works, I just let you search how to get 'offset' and 'count' value for the replaceData method !