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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(parameters); ?> %%%

Examples

Default Usage

	$defaults = 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);

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>

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.

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)

Display sub-categories as inner list items (below the parent list item) or inline. The default is true (display sub-categories below the parent list item). 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