Counting number of html tags?

[duckduckgoose]

If I have some html that looks like this:

<p>This is a paragraph:</p>

<ul>
<li>Bullet one</li>
<li>Bullet two</li>
<li>Bullet three</li>
</ul>

Is there a way to count the number of <li> tags? So that it returns 3?

[NogDog]

preg_match_all('/<li(\s[^>]*)?>/i', $text, $matches);
$li_count = count($matches[0]);