Display or retrieve the HTML dropdown list of categories.

The ‘hierarchical’ argument, which is disabled by default, will override the depth argument, unless it is true. When the argument is false, it will display all of the categories. When it is enabled it will use the value in the ‘depth’ argument.

Signature

wp_dropdown_categories( $args = '' )
args
 (string|array) Optional. Array or string of arguments to generate a categories drop-down element. See WP_Term_Query::__construct() for information on additional accepted arguments.
Default: ''

Return

(string) HTML content only if 'echo' argument is 0.

Source

function wp_dropdown_categories( $args = '' ) {
	$defaults = array(
		'show_option_all'   => '',
		'show_option_none'  => '',
		'orderby'           => 'id',
		'order'             => 'ASC',
		'show_count'        => 0,
		'hide_empty'        => 1,
		'child_of'          => 0,
		'exclude'           => '',
		'echo'              => 1,
		'selected'          => 0,
		'hierarchical'      => 0,
		'name'              => 'cat',
		'id'                => '',
		'class'             => 'postform',
		'depth'             => 0,
		'tab_index'         => 0,
		'taxonomy'          => 'category',
		'hide_if_empty'     => false,
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