How to retrieve an html element opening tag from an html string?

Question

I'm trying to retrieve <h1> opening tags from a html string. I want to include everything from <h1 to >.

Right now this is how I'm trying to do it, however it seems it's causing problems with encoding as when I print the resulting $html utf-8 characters show incorrectly:

        $dom = new DOMDocument();
        $dom->loadHTML($html);

        //Evaluate Anchor tag in HTML
        $xpath = new DOMXPath($dom);


        $elements = $xpath->evaluate("/html/body//h1");

        for ($i = 0; $i < $elements->length; $i++) {
            print_r($elements->item($i));
        }

        // save html
        $html=$dom->saveHTML();

How can I make sure it includes everything up to the > closure?

Answer 1

Not an expert, but I made this:

<h1( [^>]*(["'].*["'])\1*)?>

Here my tests:

Update 1:

<h1\s*>|(.*=['"]*[^'"]*['"]*)>

Update 2:

<h1(.+=((['"]+[^'"]*['"]+)|[0-9]+))*\s*>

I modeled what should support an h1 tag.