Retrieves a list of category objects.
Description
If you set the ‘taxonomy’ argument to ‘link_category’, the link categories will be returned instead.
See also
- get_terms(): Type of arguments that can be changed.
Parameters
$args
string|arrayoptional- Arguments to retrieve categories. See get_terms() for additional options.
taxonomy
stringTaxonomy to retrieve terms for. Default'category'
.
More Arguments from get_terms( … $args )
Array or string of arguments. See WP_Term_Query::__construct() for information on accepted arguments.Default:
''
Source
function get_categories( $args = '' ) {
$defaults = array( 'taxonomy' => 'category' );
$args = wp_parse_args( $args, $defaults );
/**
* Filters the taxonomy used to retrieve terms when calling get_categories().
*
* @since 2.7.0
*
* @param string $taxonomy Taxonomy to retrieve terms from.
* @param array $args An array of arguments. See get_terms().
*/
$args['taxonomy'] = apply_filters( 'get_categories_taxonomy', $args['taxonomy'], $args );
// Back compat.
if ( isset( $args['type'] ) && 'link' === $args['type'] ) {
_deprecated_argument(
__FUNCTION__,
'3.0.0',
sprintf(
/* translators: 1: "type => link", 2: "taxonomy => link_category" */
__( '%1$s is deprecated. Use %2$s instead.' ),
'<code>type => link</code>',
'<code>taxonomy => link_category</code>'
)
);
$args['taxonomy'] = 'link_category';
}
$categories = get_terms( $args );
if ( is_wp_error( $categories ) ) {
$categories = array();
} else {
$categories = (array) $categories;
foreach ( array_keys( $categories ) as $k ) {
_make_cat_compat( $categories[ $k ] );
}
}
return $categories;
}
Hooks
- apply_filters( ‘get_categories_taxonomy’,
string $taxonomy ,array $args ) Filters the taxonomy used to retrieve terms when calling get_categories() .
Changelog
Version | Description |
---|---|
2.1.0 | Introduced. |
List Categories and Descriptions
This example will list, in alphabetic order, all categories presented as links to the corresponding category archive. Each category description is listed after the category link.
Function only returns categories in use by posts
It is very important to note that by default, the
get_category()
will ONLY return categories that ARE IN USE. This means if no post is assigned to the category, then the category object for that category is not returned.This means if you are developer, and you created a category (maybe during testing), you should supply an argument array having the
'hide_empty' => false
in it. Check the example usage below.Get only top level categories
To get the top level categories only, set parent value to zero. This example gets link and name of top level categories.
Specific category parent title with linked menu of subcategories
– could be used in a sidebar application
If there are no categories to display,
get_categories()
will return an empty array.get all parent categories, and then based on parent id you can write a recurring function that gives you the child category of given id.
Output look like this:
A – Main category
B – Child Category
C – Child Category
D – Nested Child Category( if available )
E – Main category
F – Child Category
G – Child Category
H – Nested Child Category( if available )
Drop-down box as used in Parent category at post category page
This is the code used in the built-in category page.
The slightly altered code below will grab all categories and display them with indent for a new level (child category). The select box will have name and id attribute values of ‘select_name’. This select element will not display a default “none” as the original code was used to attach a category as a child to another category (or none).
Drop-down Box
Here’s how to create a drop-down box of the subcategories of, say, a category that archives information on past events.
This mirrors the example of the drop-down example of
wp_get_archives()
which shows how to create a drop-down box for monthly archives.Suppose the category whose subcategories you want to show is category 10, and that its category “nicename” is “archives”.