post_link_category │ filter-hook │ WP 3.5.0

Filters the category that gets used in the %category% permalink token.

Usage

add_filter( 'post_link_category', 'wp_kama_post_link_category_filter', 10, 3 );

/**
 * Function for `post_link_category` filter-hook.
 * 
 * @param WP_Term $cat  The category to use in the permalink.
 * @param array   $cats Array of all categories (WP_Term objects) associated with the post.
 * @param WP_Post $post The post in question.
 *
 * @return WP_Term
 */
function wp_kama_post_link_category_filter( $cat, $cats, $post ){

	// filter...
	return $cat;
}

$cat(WP_Term)

The category to use in the permalink.

$cats(array)

Array of all categories (WP_Term objects) associated with the post.

$post(WP_Post)

The post in question.

Changelog

Where the hook is called

$category_object = apply_filters( 'post_link_category', $cats[0], $cats, $post );

Where the hook is used in WordPress