* Nav Menu API: Template functions
/** Walker_Nav_Menu class */
require_once ABSPATH . WPINC . '/class-walker-nav-menu.php';
* Displays a navigation menu.
* @since 4.7.0 Added the `item_spacing` argument.
* @since 5.5.0 Added the `container_aria_label` argument.
* Optional. Array of nav menu arguments.
* @type int|string|WP_Term $menu Desired menu. Accepts a menu ID, slug, name, or object.
* @type string $menu_class CSS class to use for the ul element which forms the menu.
* @type string $menu_id The ID that is applied to the ul element which forms the menu.
* Default is the menu slug, incremented.
* @type string $container Whether to wrap the ul, and what to wrap it with.
* @type string $container_class Class that is applied to the container.
* Default 'menu-{menu slug}-container'.
* @type string $container_id The ID that is applied to the container. Default empty.
* @type string $container_aria_label The aria-label attribute that is applied to the container
* when it's a nav element. Default empty.
* @type callable|false $fallback_cb If the menu doesn't exist, a callback function will fire.
* Default is 'wp_page_menu'. Set to false for no fallback.
* @type string $before Text before the link markup. Default empty.
* @type string $after Text after the link markup. Default empty.
* @type string $link_before Text before the link text. Default empty.
* @type string $link_after Text after the link text. Default empty.
* @type bool $echo Whether to echo the menu or return it. Default true.
* @type int $depth How many levels of the hierarchy are to be included.
* 0 means all. Default 0.
* @type object $walker Instance of a custom walker class. Default empty.
* @type string $theme_location Theme location to be used. Must be registered with
* register_nav_menu() in order to be selectable by the user.
* @type string $items_wrap How the list items should be wrapped. Uses printf() format with
* numbered placeholders. Default is a ul with an id and class.
* @type string $item_spacing Whether to preserve whitespace within the menu's HTML.
* Accepts 'preserve' or 'discard'. Default 'preserve'.
* @return void|string|false Void if 'echo' argument is true, menu output if 'echo' is false.
* False if there are no items or no menu was found.
function wp_nav_menu( $args = array() ) {
static $menu_id_slugs = array();
'container_aria_label' => '',
'fallback_cb' => 'wp_page_menu',
'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>',
'item_spacing' => 'preserve',
$args = wp_parse_args( $args, $defaults );
if ( ! in_array( $args['item_spacing'], array( 'preserve', 'discard' ), true ) ) {
// Invalid value, fall back to default.
$args['item_spacing'] = $defaults['item_spacing'];
* Filters the arguments used to display a navigation menu.
* @param array $args Array of wp_nav_menu() arguments.
$args = apply_filters( 'wp_nav_menu_args', $args );
* Filters whether to short-circuit the wp_nav_menu() output.
* Returning a non-null value from the filter will short-circuit wp_nav_menu(),
* echoing that value if $args->echo is true, returning that value otherwise.
* @param string|null $output Nav menu output to short-circuit with. Default null.
* @param stdClass $args An object containing wp_nav_menu() arguments.
$nav_menu = apply_filters( 'pre_wp_nav_menu', null, $args );
if ( null !== $nav_menu ) {
// Get the nav menu based on the requested menu.
$menu = wp_get_nav_menu_object( $args->menu );
// Get the nav menu based on the theme_location.
$locations = get_nav_menu_locations();
if ( ! $menu && $args->theme_location && $locations && isset( $locations[ $args->theme_location ] ) ) {
$menu = wp_get_nav_menu_object( $locations[ $args->theme_location ] );
// Get the first menu that has items if we still can't find a menu.
if ( ! $menu && ! $args->theme_location ) {
$menus = wp_get_nav_menus();
foreach ( $menus as $menu_maybe ) {
$menu_items = wp_get_nav_menu_items( $menu_maybe->term_id, array( 'update_post_term_cache' => false ) );
if ( empty( $args->menu ) ) {
// If the menu exists, get its items.
if ( $menu && ! is_wp_error( $menu ) && ! isset( $menu_items ) ) {
$menu_items = wp_get_nav_menu_items( $menu->term_id, array( 'update_post_term_cache' => false ) );
* - Fall back (if one was specified), or bail.
* If no menu items were found:
* - Fall back, but only if no theme location was specified.
if ( ( ! $menu || is_wp_error( $menu ) || ( isset( $menu_items ) && empty( $menu_items ) && ! $args->theme_location ) )
&& isset( $args->fallback_cb ) && $args->fallback_cb && is_callable( $args->fallback_cb ) ) {
return call_user_func( $args->fallback_cb, (array) $args );
if ( ! $menu || is_wp_error( $menu ) ) {
if ( $args->container ) {
* Filters the list of HTML tags that are valid for use as menu containers.
* @param string[] $tags The acceptable HTML tags for use as menu containers.
* Default is array containing 'div' and 'nav'.
$allowed_tags = apply_filters( 'wp_nav_menu_container_allowedtags', array( 'div', 'nav' ) );
if ( is_string( $args->container ) && in_array( $args->container, $allowed_tags, true ) ) {
$class = $args->container_class ? ' class="' . esc_attr( $args->container_class ) . '"' : ' class="menu-' . $menu->slug . '-container"';
$id = $args->container_id ? ' id="' . esc_attr( $args->container_id ) . '"' : '';
$aria_label = ( 'nav' === $args->container && $args->container_aria_label ) ? ' aria-label="' . esc_attr( $args->container_aria_label ) . '"' : '';
$nav_menu .= '<' . $args->container . $id . $class . $aria_label . '>';
// Set up the $menu_item variables.
_wp_menu_item_classes_by_context( $menu_items );
$sorted_menu_items = array();
$menu_items_with_children = array();
foreach ( (array) $menu_items as $menu_item ) {
$sorted_menu_items[ $menu_item->menu_order ] = $menu_item;
if ( $menu_item->menu_item_parent ) {
$menu_items_with_children[ $menu_item->menu_item_parent ] = true;
// Add the menu-item-has-children class where applicable.
if ( $menu_items_with_children ) {
foreach ( $sorted_menu_items as &$menu_item ) {
if ( isset( $menu_items_with_children[ $menu_item->ID ] ) ) {
$menu_item->classes[] = 'menu-item-has-children';
unset( $menu_items, $menu_item );
* Filters the sorted list of menu item objects before generating the menu's HTML.
* @param array $sorted_menu_items The menu items, sorted by each menu item's menu order.
* @param stdClass $args An object containing wp_nav_menu() arguments.
$sorted_menu_items = apply_filters( 'wp_nav_menu_objects', $sorted_menu_items, $args );
$items .= walk_nav_menu_tree( $sorted_menu_items, $args->depth, $args );
unset( $sorted_menu_items );
if ( ! empty( $args->menu_id ) ) {
$wrap_id = $args->menu_id;
$wrap_id = 'menu-' . $menu->slug;
while ( in_array( $wrap_id, $menu_id_slugs, true ) ) {
if ( preg_match( '#-(\d+)$#', $wrap_id, $matches ) ) {
$wrap_id = preg_replace( '#-(\d+)$#', '-' . ++$matches[1], $wrap_id );
$wrap_id = $wrap_id . '-1';
$menu_id_slugs[] = $wrap_id;
$wrap_class = $args->menu_class ? $args->menu_class : '';
* Filters the HTML list content for navigation menus.
* @param string $items The HTML list content for the menu items.
* @param stdClass $args An object containing wp_nav_menu() arguments.
$items = apply_filters( 'wp_nav_menu_items', $items, $args );
* Filters the HTML list content for a specific navigation menu.
* @param string $items The HTML list content for the menu items.
* @param stdClass $args An object containing wp_nav_menu() arguments.
$items = apply_filters( "wp_nav_menu_{$menu->slug}_items", $items, $args );
// Don't print any markup if there are no items at this point.
$nav_menu .= sprintf( $args->items_wrap, esc_attr( $wrap_id ), esc_attr( $wrap_class ), $items );
$nav_menu .= '</' . $args->container . '>';
* Filters the HTML content for navigation menus.
* @param string $nav_menu The HTML content for the navigation menu.
* @param stdClass $args An object containing wp_nav_menu() arguments.
$nav_menu = apply_filters( 'wp_nav_menu', $nav_menu, $args );
* Adds the class property classes for the current context, if applicable.
* @global WP_Query $wp_query WordPress Query object.
* @global WP_Rewrite $wp_rewrite WordPress rewrite component.
* @param array $menu_items The current menu item objects to which to add the class property information.
function _wp_menu_item_classes_by_context( &$menu_items ) {
global $wp_query, $wp_rewrite;
$queried_object = $wp_query->get_queried_object();
$queried_object_id = (int) $wp_query->queried_object_id;
$active_ancestor_item_ids = array();
$active_parent_item_ids = array();
$active_parent_object_ids = array();
$possible_taxonomy_ancestors = array();
$possible_object_parents = array();
$home_page_id = (int) get_option( 'page_for_posts' );
if ( $wp_query->is_singular && ! empty( $queried_object->post_type ) && ! is_post_type_hierarchical( $queried_object->post_type ) ) {
foreach ( (array) get_object_taxonomies( $queried_object->post_type ) as $taxonomy ) {
if ( is_taxonomy_hierarchical( $taxonomy ) ) {
$term_hierarchy = _get_term_hierarchy( $taxonomy );
$terms = wp_get_object_terms( $queried_object_id, $taxonomy, array( 'fields' => 'ids' ) );
if ( is_array( $terms ) ) {
$possible_object_parents = array_merge( $possible_object_parents, $terms );
$term_to_ancestor = array();
foreach ( (array) $term_hierarchy as $anc => $descs ) {
foreach ( (array) $descs as $desc ) {
$term_to_ancestor[ $desc ] = $anc;
foreach ( $terms as $desc ) {
$possible_taxonomy_ancestors[ $taxonomy ][] = $desc;
if ( isset( $term_to_ancestor[ $desc ] ) ) {
$_desc = $term_to_ancestor[ $desc ];
unset( $term_to_ancestor[ $desc ] );
} while ( ! empty( $desc ) );
} elseif ( ! empty( $queried_object->taxonomy ) && is_taxonomy_hierarchical( $queried_object->taxonomy ) ) {
$term_hierarchy = _get_term_hierarchy( $queried_object->taxonomy );
$term_to_ancestor = array();
foreach ( (array) $term_hierarchy as $anc => $descs ) {
foreach ( (array) $descs as $desc ) {
$term_to_ancestor[ $desc ] = $anc;
$desc = $queried_object->term_id;
$possible_taxonomy_ancestors[ $queried_object->taxonomy ][] = $desc;
if ( isset( $term_to_ancestor[ $desc ] ) ) {
$_desc = $term_to_ancestor[ $desc ];
unset( $term_to_ancestor[ $desc ] );
} while ( ! empty( $desc ) );
$possible_object_parents = array_filter( $possible_object_parents );
$front_page_url = home_url();
$front_page_id = (int) get_option( 'page_on_front' );
$privacy_policy_page_id = (int) get_option( 'wp_page_for_privacy_policy' );
foreach ( (array) $menu_items as $key => $menu_item ) {
$menu_items[ $key ]->current = false;
$classes = (array) $menu_item->classes;
$classes[] = 'menu-item';
$classes[] = 'menu-item-type-' . $menu_item->type;
$classes[] = 'menu-item-object-' . $menu_item->object;
// This menu item is set as the 'Front Page'.
if ( 'post_type' === $menu_item->type && $front_page_id === (int) $menu_item->object_id ) {
$classes[] = 'menu-item-home';
// This menu item is set as the 'Privacy Policy Page'.
if ( 'post_type' === $menu_item->type && $privacy_policy_page_id === (int) $menu_item->object_id ) {
$classes[] = 'menu-item-privacy-policy';
// If the menu item corresponds to a taxonomy term for the currently queried non-hierarchical post object.
if ( $wp_query->is_singular && 'taxonomy' === $menu_item->type
&& in_array( (int) $menu_item->object_id, $possible_object_parents, true )
$active_parent_object_ids[] = (int) $menu_item->object_id;
$active_parent_item_ids[] = (int) $menu_item->db_id;
$active_object = $queried_object->post_type;
// If the menu item corresponds to the currently queried post or taxonomy object.
$menu_item->object_id == $queried_object_id
( ! empty( $home_page_id ) && 'post_type' === $menu_item->type
&& $wp_query->is_home && $home_page_id == $menu_item->object_id )
|| ( 'post_type' === $menu_item->type && $wp_query->is_singular )
|| ( 'taxonomy' === $menu_item->type
&& ( $wp_query->is_category || $wp_query->is_tag || $wp_query->is_tax )
&& $queried_object->taxonomy == $menu_item->object )
$classes[] = 'current-menu-item';
$menu_items[ $key ]->current = true;
$_anc_id = (int) $menu_item->db_id;
( $_anc_id = (int) get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) )
&& ! in_array( $_anc_id, $active_ancestor_item_ids, true )
$active_ancestor_item_ids[] = $_anc_id;
if ( 'post_type' === $menu_item->type && 'page' === $menu_item->object ) {
// Back compat classes for pages to match wp_page_menu().
$classes[] = 'page_item';
$classes[] = 'page-item-' . $menu_item->object_id;
$classes[] = 'current_page_item';
$active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
$active_parent_object_ids[] = (int) $menu_item->post_parent;
$active_object = $menu_item->object;
// If the menu item corresponds to the currently queried post type archive.
'post_type_archive' === $menu_item->type
&& is_post_type_archive( array( $menu_item->object ) )
$classes[] = 'current-menu-item';
$menu_items[ $key ]->current = true;
$_anc_id = (int) $menu_item->db_id;
( $_anc_id = (int) get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) )
&& ! in_array( $_anc_id, $active_ancestor_item_ids, true )
$active_ancestor_item_ids[] = $_anc_id;
$active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
// If the menu item corresponds to the currently requested URL.
} elseif ( 'custom' === $menu_item->object && isset( $_SERVER['HTTP_HOST'] ) ) {
$_root_relative_current = untrailingslashit( $_SERVER['REQUEST_URI'] );
// If it's the customize page then it will strip the query var off the URL before entering the comparison block.
if ( is_customize_preview() ) {
$_root_relative_current = strtok( untrailingslashit( $_SERVER['REQUEST_URI'] ), '?' );
$current_url = set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_root_relative_current );
$raw_item_url = strpos( $menu_item->url, '#' ) ? substr( $menu_item->url, 0, strpos( $menu_item->url, '#' ) ) : $menu_item->url;
$item_url = set_url_scheme( untrailingslashit( $raw_item_url ) );
$_indexless_current = untrailingslashit( preg_replace( '/' . preg_quote( $wp_rewrite->index, '/' ) . '$/', '', $current_url ) );
urldecode( $current_url ),
urldecode( $_indexless_current ),
urldecode( $_root_relative_current ),
if ( $raw_item_url && in_array( $item_url, $matches, true ) ) {
$classes[] = 'current-menu-item';
$menu_items[ $key ]->current = true;
$_anc_id = (int) $menu_item->db_id;
( $_anc_id = (int) get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) )
&& ! in_array( $_anc_id, $active_ancestor_item_ids, true )
$active_ancestor_item_ids[] = $_anc_id;
if ( in_array( home_url(), array( untrailingslashit( $current_url ), untrailingslashit( $_indexless_current ) ), true ) ) {
// Back compat for home link to match wp_page_menu().
$classes[] = 'current_page_item';