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Function Reference/get categories

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Description

Returns an array of category objects matching the query parameters.

Arguments are pretty much the same as wp_list_categories and can be passed as either array or in query syntax.

Usage

 <?php $categories = get_categories( $args ); ?> 

Default Usage

 <?php $args = array(
    'type'                     => 'post',
    'child_of'                 => 0,
    'orderby'                  => 'name',
    'order'                    => 'ASC',
    'hide_empty'               => true,
    'include_last_update_time' => false,
    'hierarchical'             => 1,
    'exclude'                  => ,
    'include'                  => ,
    'number'                   => ,
    'pad_counts'               => false );?>

Parameters

type 
(string) Type of category to retreive
  • post - default
  • link
child_of 
(integer) Only display categories that are children of the category identified by its ID. There is no default for this parameter. If the parameter is used, the hide_empty parameter is set to false.
parent 
(integer) Display categories whose parent category is identified by its ID. Works like the 'child_of' parameter. There is no default for this parameter. [In 2.8.4]
orderby 
(string) Sort categories alphabetically or by unique category ID. The default is sort by Category ID. Valid values:
  • ID - default
  • name
order 
(string) Sort order for categories (either ascending or descending). The default is ascending. Valid values:
  • asc - default
  • desc
hide_empty 
(boolean) Toggles the display of categories with no posts. The default is true (hide empty categories). Valid values:
  • 1 (true) - default
  • 0 (false)
include_last_update_time 
(boolean) Uncertain what this doesies|the example]].
  • 1 (true)
  • 0 (false) -- default
hierarchical 
(boolean) When true, the results will include sub-categories that are empty, as long as those sub-categories have sub-categories that are not empty. The default is true. Valid values:
  • 1 (true) - default
  • 0 (false)
exclude 
(string) Excludes one or more categories from the list generated by wp_list_categories. This parameter takes a comma-separated list of categories by unique ID, in ascending order. See the example.
include 
(string) Only include certain categories in the list generated by wp_list_categories. This parameter takes a comma-separated list of categories by unique ID, in ascending order. See the example.
  • list - default.
  • none
number 
(string) The number of categories to return
pad_counts 
(boolean) Calculates link or post counts by including items from child categories. Valid values:
  • 1 (true)
  • 0 (false) - default

Examples

Dropdown Box

Here's how to create a dropdown box of the subcategories of, say, a category that archives information on past events. This mirrors the example of the dropdown example of wp_get_archives which shows how to create a dropdown box for monthly archives.

Suppose the category whose subcategories you want to show is category 10, and that its category "nicename" is "archives". 

<select name="event-dropdown" onchange='document.location.href=this.options[this.selectedIndex].value;'> 
 <option value=""><?php echo attribute_escape(__('Select Event')); ?></option> 
 <?php 
  $categories=  get_categories('child_of=10'); 
  foreach ($categories as $cat) {
  	$option = '<option value="/category/archives/'.$cat->category_nicename.'">';
	$option .= $cat->cat_name;
	$option .= ' ('.$cat->category_count.')';
	$option .= '</option>';
	echo $option;
  }
 ?>
</select>
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