WP Engineer - WordPress News, Hacks, Tipps, Tutorials, Plugins and Themes

Numbering your comments, pingbacks, trackbacks or all

February 3rd, 2009 by Frank • WordPress Hacks • 20 Comments

Since WordPress 2.7 exists an API for the comment area. Thereby you can purge the PHP-portion within comments.php. Jean-Baptiste shows a simple solution to count comments. This solution is very well known and get used pretty much since the first release of WordPress. But if you like to have a filter, which counts only the trackbacks or only the comments, then this solutions is worthless. Besides that, the How To is pretty poor and PHP-rookies could have troubles with it.

Relating to this and because of many questions about this topic I show you two simple functions, which you insert in your functions.php of your theme. Normally they get used as output in your comments.php.

/**
 * count for Trackback, pingback, comment, pings
 *
 * use it:
 * fb_comment_type_count('ping');
 * fb_comment_type_count('comment');
 */
if ( !function_exists('fb_comment_type_count') ) {
	function fb_get_comment_type_count( $type='all', $zero = false, $one = false, $more = false, $post_id = 0) {
		global $cjd_comment_count_cache, $id, $post;

		if ( !$post_id )
			$post_id = $post->ID;
		if ( !$post_id )
			return;

		if ( !isset($cjd_comment_count_cache[$post_id]) ) {
			$p = get_post($post_id);
			$p = array($p);
			update_comment_type_cache($p);
		}
		;
		if ( $type == 'pingback' || $type == 'trackback' || $type == 'comment' )
			$count = $cjd_comment_count_cache[$post_id][$type];
		elseif ( $type == 'pings' )
			$count = $cjd_comment_count_cache[$post_id]['pingback'] + $cjd_comment_count_cache[$post_id]['trackback'];
		else
			$count = array_sum((array) $cjd_comment_count_cache[$post_id]);

		return apply_filters('fb_get_comment_type_count', $count);
	}

	// comment, trackback, pingback, pings, all
	function fb_comment_type_count( $type='all', $zero = false, $one = false, $more = false, $post_id = 0 ) {

		$number = fb_get_comment_type_count( $type, $zero, $one, $more, $post_id );

		if ( $number > 1 )
			$output = str_replace('%', number_format_i18n($number), ( false === $more ) ? __('% Comments') : $more);
		elseif ( $number == 0 )
			$output = ( false === $zero ) ? __('No Comments') : $zero;
		else // must be one
			$output = ( false === $one ) ? __('1 Comment') : $one;

		echo apply_filters('fb_comment_type_count', $output, $number);
	}
}

if ( !function_exists('fb_update_comment_type_cache') ) {
	function fb_update_comment_type_cache(&$queried_posts) {
		global $cjd_comment_count_cache, $wpdb;

		if ( !$queried_posts )
			return $queried_posts;

		foreach ( (array) $queried_posts as $post )
			if ( !isset($cjd_comment_count_cache[$post->ID]) )
				$post_id_list[] = $post->ID;

		if ( $post_id_list ) {
			$post_id_list = implode(',', $post_id_list);

			foreach ( array('', 'pingback', 'trackback') as $type ) {
				$counts = $wpdb->get_results("SELECT ID, COUNT( comment_ID ) AS ccount
							FROM $wpdb->posts
							LEFT JOIN $wpdb->comments ON ( comment_post_ID = ID AND comment_approved = '1' AND comment_type='$type' )
							WHERE post_status = 'publish' AND ID IN ($post_id_list)
							GROUP BY ID");

				if ( $counts ) {
					if ( '' == $type )
						$type = 'comment';
					foreach ( $counts as $count )
						$cjd_comment_count_cache[$count->ID][$type] = $count->ccount;
				}
			}
		}

		return $queried_posts;
	}

	add_filter('the_posts', 'fb_update_comment_type_cache');
}

If both functions in your theme are available, the usage of the 3 forms comments, trackbacks and pingbacks could look like this:

if ( function_exists('wp_list_comments') ) {

	// WP 2.7 comment loop
	if ( have_comments() ) { ?>

		<?php if ( empty($comments_by_type['comment']) ) { ?>
			<h2 id="comments"><?php fb_comment_type_count( 'comment' ); ?></h2>
			<ol class="commentlist">
				<?php wp_list_comments( 'type=comment&callback=fb_theme_comment' ); ?>
			</ol>
		<?php } ?>

		<?php
		if ( function_exists( 'fb_comment_type_count' ) ) {
			// alternative type pings for trackback + pingback
			if ( empty($comments_by_type['$post_id']) ) { ?>
				<h2 id="pingback"><?php fb_comment_type_count( 'pingback', 'No Pingback', 'OnePingback', '% Pingbacks' ); ?></h2>
				<ol class="pingbacklist">
					<?php wp_list_comments('type=pingback'); ?>
				</ol>
			<?php } ?>

			<?php
			// alternative type pings for trackback + pingback
			if ( empty($comments_by_type['trackback']) ) { ?>
				<h2 id="trackback"><?php fb_comment_type_count( 'trackback', 'No Trackback', 'One Trackback', '% Trackbacks' ); ?></h2>
				<ol class="trackbacklist">
					<?php wp_list_comments('type=trackback'); ?>
				</ol>
			<?php }
		} ?>

		<div class="navigation nav_comments">
			<div class="alignleft"><?php previous_comments_link() ?></div>
			<div class="alignright"><?php next_comments_link() ?></div>
		</div>

	<?php } else {
		// this is displayed if there are no comments so far
	} ?>