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This plugin provides functions to retrieve the parent category of any particular post should it be assigned to a sub category of that parent category.
Using this feature, the plugin is also able to modify the WordPress Loop to redirect any category page generation to the parent category. This is especially useful when theme developers want to be able to specify category-x.php templates and have all related posts, be it those assigned to the category or the sub categories use that template for page generation.
So for example the current category structure is as follows.
<ul>
<li>Main Category (has category-x.php template)
<ul>
<li>Sub Category 1</li>
<li>Sub Category 2</li>
</ul>
</li>
</ul>
A post is assigned to “Sub Category 2”.
When the post is requested the plugin will automatically detect if it has a parent category. If so, it will modify the WP variables to set the current category as the parent category and add a new variable stating the actual category of the post. This affects the WordPress Loop to category-x.php template defined for the parent
<h3>Usable Commands for Theme Developers</h3>
The PHP commands for theme developers to use are pretty straight forward.
get_category_child() returns the current post child category ID.
is_parent() checks if the current post is at the parent category.
get_category_title($id) gets the title of the category that is $id.
get_category_parent() returns the current post’s parent category ID.

Elevate Parent Category Template

Elevates parent category template to top of WordPress Loop.

The archives within WordPress are pretty limited in a sense that they do not offer much configuration beyond what they do. Date based will be date based, like category based archives will only display categories. This plugin mitigates the issue by giving date based archives the ability to list content by categories as well.
This is done via modification of the rewrite rules to allow for the ability to have permalinks like http://yourblog.com/2008/in-blog/. This basically is a date based archive that shows only entries from the “blog” category.
This plugin can also work without the usage of rewrite rules. It currently supports date based archives for years and months.
<h3>Usable Commands for Theme Developers</h3>
The PHP commands for theme developers to use are pretty straight forward.
cba_get_category_id() returns the current category ID of the archive.
cba_the_year() returns the current year of the date based archive.
cba_the_month() returns the current month of the date based archive.
cba_auto_thedate() gets the string representation of the date.
cba_get_year_link($year) returns the permalink for the year archive based on the current category.

Category Based Archives

Allows date based archives to be listed by category.

Elevate Parent Category Template vs Category Based Archives