Habitually Good

This post only applies to people who are running a WordPress blog and have access to editing their template pages. A few days ago, I had a requirement where I wanted to prevent posts in certain categories from showing up on my blog’s main index page. There are a couple of ways mentioned on the WordPress Codex for this. However, try as I may, I couldn’t get them to work after several attempts (till I read the documentation very carefully). If you are facing the same problem, read on.

Note: The following require making changes to the templates files of your blog and you can potentially make your blog unreadable. Please proceed at your own risk. It is imperative to take a backup of all the template files so that if you mess up, you can restore the backup.

For the purpose of this article, I assume that you know how to edit your template file and have a basic understanding of The Loop in WordPress. Just follow the link to refresh your memories.

Method 1: in_category() function

There are two ways through which you can achieve excluding a category from your main index page. If you followed the link for The Loop and read through to the end of the page, you already know the first one. Within The Loop, you can simply add a line of PHP code which looks something like this:

<?php if (in_category(’3′)) continue; ?>

By inserting this call, you are essentially telling WordPress to skip over displaying any posts which are in the category with CategoryID 3. This worked for me the first time, but there was a problem with it.

If you read the page carefully, then it is mentioned there that even though we skip over the post within a certain category, it still gets counted. So, in your settings if you have defined the maximum number of posts to be displayed as 10, and in your last 5 posts to your blog, 4 belong to the category you want to exclude, then your main index page will only display 6 posts.

Method 2: query_posts() function

This was not acceptable to me, so I looked at the other documented method of excluding a category from my Main Index page: using the Query_posts function. This function, when called before The Loop, creates a new set of posts for The Loop to work on. While there are many fun things that you can do with this function, our interest is in excluding categories. To exclude the category with Category ID 3, we should call this function as shown before The Loop begins:

<?php query_posts($query_string . “&cat=-3″); ?>

This allows you to exclude the undesired categories and yet be able to display the desired number of posts. Even this method is prone to a problem. This only works for posts which ONLY have category 3 (in above example). So, if you have a post which is filed under category 3 as well as 4, it will still show up. This I can live with; I don’t file the posts I want to exclude under more than one category.

There is one gotcha with this method. It doesn’t work with the old version of The Loop. Yes, if you were a careful reader, you would have noticed that there are a couple of versions of The Loop shown in the Codex articles. For the query_posts method to work, the beginning of your Loop must look like this:

<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>

This was my main problem. I was using an old theme and it had the old method of iterating The Loop.

Winding Up

Of course, these changes have to be made to all the template files in your theme which use The Loop and where you don’t want to show the posts within the concerned category; except the Category Page template of course, because you want to at least be able to access the excluded posts from their category pages.

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