WordPress Custom Fields: Listing A Series Of Posts

By Justin Tadlock on November 1, 2007

This is an updated version of this article. If you’re looking for the older version, see page 2.

Do you write long series of posts? Do you have a bunch of articles that definitely need to be linked together? This WordPress custom fields technique will allow you to do that without a lot of hassle. Basically, this is a simple, customized related posts script. It checks to see whether a post is in a series, then lists all the posts in the series.

The WordPress custom fields tutorial series uses this code for listing posts. You can scroll to the bottom of this entry to see what the outcome looks like.

The reason I’m writing this tutorial is precisely because of the WordPress custom fields series. After three posts, and going back to each previous post to add a link to the new post, I realized that this was only going to get more tedious and time-consuming each time I wrote another article in the series. So, this idea was born from that.

How to set up your posts

You’ll probably want more than one post. This is a series after all.

Create a custom field key called Series first. Give it a unique custom field value. You should give every article in the series this exact same key and value.

This is all you have to do on the Write Post screen.

Adding the series function

Open your theme’s functions.php file and paste this code into it.

<?php
function article_series() {
	global $post;
	$series = get_post_meta($post->ID, 'Series', true);
	if($series) :
		$args = array(
			'numberposts' => -1,
			'meta_key' => 'Series',
			'meta_value' => $series,
		);
		$series_posts = get_posts($args);
		if($series_posts) :
			$class = preg_replace("/[^a-z0-9\\040\\.\\-\\_\\\\]/i", "", $series);
			$class = strtolower(str_replace(array(' ', '&nbsp;'), '-', $class));
			echo '<div class="series series-' . $class . '"><h4 class="series-title">' . __('Articles in this series') . '</h4><ul>';
			foreach($series_posts as $serial) :
				if($serial->ID == $post->ID)
					echo '<li class="current-post">' . $serial->post_title . '</li>';
				else
					echo '<li><a href="' . get_permalink($serial->ID) . '" title="' . str_replace('"', '"', $serial->post_title) . '">' . str_replace('"', '"', $serial->post_title) . '</a></li>';
			endforeach;
			echo '</ul></div>';
		endif;
	endif;
}
?>

Add your function to your single post template

You can add this to single.php and/or page.php. If your theme has a hook after posts/pages, you can even hook it to that with without touching a template file (ask your theme author about this).

So, open your file and add this somewhere in it before the call for comments_template(), preferrably somewhere within the Loop.

<?php article_series(); ?>

That’s it, and you’re done. Just save everything and check out your series list at the end of posts within that series. You can create as many of these as you like.

Final thoughts

Now, that should do it. You can always tweak this script to better apply to your needs. There are also some other uses you can extract from this article.

I’m already loving this because I won’t have to go back to the previous three posts in this series just to link back to this article. Life is much simpler now.

As always, remember to subscribe to the feed to stay updated on the WordPress custom fields tutorial series. I have a few more ideas up my sleeve and am ready to post them as soon as I finish testing.

Let me know if you liked this tutorial. I’m always open to feedback and looking for new ideas to implement.

Pages: 1 2

Posted in WordPress | Tagged Custom Fields, WordPress

Articles in this series