PHP preg_replace - 删除ul，li标签之间的BR标签

I would like to create a regex which will be strip all BR tags between ul/ol li tags. For example:

Test<br>
<ul>
<li>
Test<br>
</li>
</ul>

And I want to get this result:

Test<br>
<ul>
<li>
Test
</li>
</ul>

I tried using this code:

    $param_array['description'] = preg_replace('/(?<=<ul>|<\/li>)([\s*<br>\s*|\s*<br\/>\s*|\s*<br \/>\s*]+)(?=<\/ul>|<li>)/is', "$1$3", $param_array['description']);
    $param_array['description'] = preg_replace('/(?<=<ol>|<\/li>)([\s*<br>\s*|\s*<br\/>\s*|\s*<br \/>\s*]+)(?=<\/ol>|<li>)/is', "$1$3", $param_array['description']);

but it doesn't work. Anyone can help me?

Use the str_replace() function to remove any instances of
:)

<?php 
    $html = "Test<br>
    <ul>
    <li>
    Test<br>
    </li>
    </ul>";

    $without_breaks = str_replace(array('<br>', '&', '"'), ' ', $html);

?>

How about simply using CSS: li br {display:none;}