note 86463 added to function.strip-tags

It's come to my attention that PHP's strip_tags has been doing something funky to some video embed codes that our members submit. I'm not sure the exact situation, but whenever there is a <param> tag that is very long, strip_tags() will completely remove the tag even though it's specified as an allowable tag. Here's an example of the existing problem: <?php // a single very long <param> tag $html =<<<EOF <param name="flashVars" value="skin=http%3A//cdn-i.dmdentertainm ...[snip]... vie%20of%20All-Time"/> EOF; echo strip_tags($html, '<param>'); // this outputs an empty string ?> This is the function I built to fix and extend the functionality of strip_tags(). The args are: - $i_html - the HTML string to be parsed - $i_allowedtags - an array of allowed tag names - $i_trimtext - whether or not to strip all text outside of the allowed tags <?php function real_strip_tags($i_html, $i_allowedtags = array(), $i_trimtext = FALSE) { if (!is_array($i_allowedtags)) $i_allowedtags = !empty($i_allowedtags) ? array($i_allowedtags) : array(); $tags = implode('|', $i_allowedtags); if (empty($tags)) $tags = '[a-z]+'; preg_match_all('@</?\s*(' . $tags . ')(\s+[a-z_]+=(\'[^\']+\'|"[^"]+"))*\s*/?>@i', $i_html, $matches); $full_tags = $matches[0]; $tag_names = $matches[1]; foreach ($full_tags as $i => $full_tag) { if (!in_array($tag_names[$i], $i_allowedtags)) if ($i_trimtext) unset($full_tags[$i]); else $i_html = str_replace($full_tag, '', $i_html); } return $i_trimtext ? implode('', $full_tags) : $i_html; } ?> And here's an example with the a block of full video embed code with <object><embed><param> and some extraneous HTML: <?php $html =<<<EOF <em><div><object type="application/x-shock ...[snip]... me.html">Wal-Mart Makes The Worst Movie of All-Time</a> -- powered by whatever</div></em> EOF; $good_html = real_strip_tags($html, array('object', 'embed', 'param'), TRUE); ?> Now $good_html contains only the specified tags and none of the "powered by" type text. I hope someone finds this as useful as I needed it to be. :) ---- Server IP: 216.92.131.65 Probable Submitter: 208.247.75.49 ---- Manual Page -- http://www.php.net/manual/en/function.strip-tags.php Edit -- https://master.php.net/note/edit/86463 Del: integrated -- https://master.php.net/note/delete/86463/integrated Del: useless -- https://master.php.net/note/delete/86463/useless Del: bad code -- https://master.php.net/note/delete/86463/bad+code Del: spam -- https://master.php.net/note/delete/86463/spam Del: non-english -- https://master.php.net/note/delete/86463/non-english Del: in docs -- https://master.php.net/note/delete/86463/in+docs Del: other reasons-- https://master.php.net/note/delete/86463 Reject -- https://master.php.net/note/reject/86463 Search -- https://master.php.net/manage/user-notes.php