Add CDATA to script- and style-tags via regex using PHPs output buffering

function.wrap-scripts-and-styles-into-cdata.php

<?php

/* do this if MIME type is 'application/xhtml+xml' */
ob_start(function ($buffer) {
	$replacer = array(
		'/(<script[^<>]*>)([^<>]+)(<\/script>)/' => '$1<![CDATA[ $2 ]]>$3',
		'/(<style[^<>]*>)([^<>]+)(<\/style>)/' => '$1<![CDATA[ $2 ]]>$3',

	/* more replaces may follow, like:
	 * replace ampersand-characters, which are not part of an entity or within a CDATA-block
		'/&(?!(?:[a-zA-Z][a-zA-Z0-9]*|#\d+);)(?!(?>(?:(?!<!\[CDATA\[|\]\]>).)*)\]\]>)/s' => '&#38;',
	 * replace html-entities with xml entities
		'/&nbsp;/' => '&#160;',
	 */

	);
	return preg_replace(array_keys($replacer), array_values($replacer), $buffer);
});



/* a script-block like
 
<script type="text/javascript">
$(document).ready(function() {
	$('.hover').bind('touchstart touchend', function(e) {
		e.preventDefault();
		$(this).toggleClass('hover_effect');
	});
});
</script>
 
 * will translate to
 
<script type="text/javascript"><![CDATA[ 
$(document).ready(function() {
	$('.hover').bind('touchstart touchend', function(e) {
		e.preventDefault();
		$(this).toggleClass('hover_effect');
	});
});
]]></script>
 
*/

Add CDATA to script- and style-tags via regex using PHPs output buffering

This snippet can be used to sanitize HTML when delivering it as XHTML. Everything (at least there must be one character) between script/style-tags is enclosed by a CDATA-block.

The whole functionality is provided as a callback function to ob_start(), which should be used before any output. The use of ob_flush(), ob_clean() or something is optional as the buffer will be sent on script end anyway.