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function is not described

Walker_CategoryDropdown::start_el() public WP 2.1.0

Starts the element output.

{} It's a method of the class: Walker_CategoryDropdown{}

Hooks from the method
Return

null. Null. Nothing.

Usage

$Walker_CategoryDropdown = new Walker_CategoryDropdown();
$Walker_CategoryDropdown->start_el( $output, $category, $depth, $args, $id );
$output(string) (required)
Used to append additional content (passed by reference).
$category(WP_Term) (required)
Category data object.
$depth(int)
Depth of category. Used for padding.
$args(array)
Uses 'selected', 'show_count', and 'value_field' keys, if they exist. See wp_dropdown_categories().
$id(int)
ID of the current category.
Default: 0 (unused)

Notes

  • See: Walker::start_el()

Changelog

Since 2.1.0 Introduced.

Code of Walker_CategoryDropdown::start_el() WP 5.7.1

<?php
public function start_el( &$output, $category, $depth = 0, $args = array(), $id = 0 ) {
	$pad = str_repeat( '&nbsp;', $depth * 3 );

	/** This filter is documented in wp-includes/category-template.php */
	$cat_name = apply_filters( 'list_cats', $category->name, $category );

	if ( isset( $args['value_field'] ) && isset( $category->{$args['value_field']} ) ) {
		$value_field = $args['value_field'];
	} else {
		$value_field = 'term_id';
	}

	$output .= "\t<option class=\"level-$depth\" value=\"" . esc_attr( $category->{$value_field} ) . '"';

	// Type-juggling causes false matches, so we force everything to a string.
	if ( (string) $category->{$value_field} === (string) $args['selected'] ) {
		$output .= ' selected="selected"';
	}
	$output .= '>';
	$output .= $pad . $cat_name;
	if ( $args['show_count'] ) {
		$output .= '&nbsp;&nbsp;(' . number_format_i18n( $category->count ) . ')';
	}
	$output .= "</option>\n";
}