PreprocessCommentContentin?WordPress

Ive put a great amount of effort into making sure the?comment system on this blog is fast?and feature-filled. ?The comment system is AJAX-based so you dont need to worry about page refreshes. ?You can also post links to GitHub gists, CodeP

I&＃8217;ve put a great amount of effort into making sure the?comment system on this blog is fast?and feature-filled. ?The comment system is AJAX-based so you don&＃8217;t need to worry about page refreshes. ?You can also post links to GitHub gists, CodePen pens, and JSFiddle fiddles and see them rendered within the comment. ?Those tasks I accomplish?after a comment has been registered in the?system. ?But what if you want to?modify comment content before it is processed, and subsequently marked as SPAM or scrubbed? ?That&＃8217;s super easy with WordPress hooks!

The PHP

The preprocess_comment hook allows us to get at the comment data before it is processed. ?Here is how I use this hook, wrapping?`text` strings in elements and encoding angle characters in

?elements:

// Manage comment submissions
function preprocess_new_comment($commentdata) {
	// Replace `code` with code
	$commentdata['comment_content'] = preg_replace("/`(.*)`/Um", "$1", $commentdata['comment_content']);
	// Ensure that code inside pre's is allowed
	preg_match_all("/(.*)<\/pre>/", $commentdata['comment_content'], $pre_matches); // $2
	foreach($pre_matches as $match) {
		$immediate_match = str_replace(array('<', '>'), array('<', '>'), $match[2]);
		$commentdata['comment_content'] = str_replace($match[2], $immediate_match, $commentdata['comment_content']);
	}
	// Return
	return $commentdata;
}
add_action('preprocess_comment', 'preprocess_new_comment');

This snippet?should be added to functions.php, as you would expect of a WordPress theme enhancement.
I love the WordPress hook system &＃8212; it makes the CMS incredibly powerful and?customizable. ?I also use this hook to prevent WordPress comment SPAM. ?And since many users place HTML code in my comments, it&＃8217;s important?I encode those angle characters properly. ?In the end, you never know what your user will submit and what each site will accept &＃8212; use this?WordPress hook to take control!
Read the full article at:  Preprocess Comment Content in WordPress