Walker_CategoryDropdown

17class Walker_CategoryDropdown extends Walker {18 19	/**20	 * What the class handles.21	 *22	 * @since 2.1.023	 * @var string24	 *25	 * @see Walker::$tree_type26	 */27	public $tree_type = 'category';28 29	/**30	 * Database fields to use.31	 *32	 * @since 2.1.033	 * @todo Decouple this34	 * @var string[]35	 *36	 * @see Walker::$db_fields37	 */38	public $db_fields = array(39		'parent' => 'parent',40		'id'     => 'term_id',41	);42 43	/**44	 * Starts the element output.45	 *46	 * @since 2.1.047	 * @since 5.9.0 Renamed `$category` to `$data_object` and `$id` to `$current_object_id`48	 *              to match parent class for PHP 8 named parameter support.49	 *50	 * @see Walker::start_el()51	 *52	 * @param string  $output            Used to append additional content (passed by reference).53	 * @param WP_Term $data_object       Category data object.54	 * @param int     $depth             Depth of category. Used for padding.55	 * @param array   $args              Uses 'selected', 'show_count', and 'value_field' keys, if they exist.56	 *                                   See wp_dropdown_categories().57	 * @param int     $current_object_id Optional. ID of the current category. Default 0.58	 */59	public function start_el( &$output, $data_object, $depth = 0, $args = array(), $current_object_id = 0 ) {60		// Restores the more descriptive, specific name for use within this method.61		$category = $data_object;62 63		$pad = str_repeat( '&nbsp;', $depth * 3 );64 65		/** This filter is documented in wp-includes/category-template.php */66		$cat_name = apply_filters( 'list_cats', $category->name, $category );67 68		if ( isset( $args['value_field'] ) && isset( $category->{$args['value_field']} ) ) {69			$value_field = $args['value_field'];70		} else {71			$value_field = 'term_id';72		}73 74		$output .= "\t<option class=\"level-$depth\" value=\"" . esc_attr( $category->{$value_field} ) . '"';75 76		// Type-juggling causes false matches, so we force everything to a string.77		if ( (string) $category->{$value_field} === (string) $args['selected'] ) {78			$output .= ' selected="selected"';79		}80		$output .= '>';81		$output .= $pad . $cat_name;82		if ( $args['show_count'] ) {83			$output .= '&nbsp;&nbsp;(' . number_format_i18n( $category->count ) . ')';84		}85		$output .= "</option>\n";86	}87}