WordPress at a glance
filter is not described

nav_menu_css_class filter-hook . WP 3.0.0

Filters the CSS classes applied to a menu item's list item element.


add_filter( 'nav_menu_css_class', 'filter_function_name_8599', 10, 4 );
function filter_function_name_8599( $classes, $item, $args, $depth ){
	// filter...

	return $classes;
Array of the CSS classes that are applied to the menu item's <li> element.
The current menu item.
An object of wp_nav_menu() arguments.
Depth of menu item. Used for padding.


Since 3.0.0 Introduced.
Since 4.1.0 The $depth parameter was added.

Where the hook is called

wp-includes/class-walker-nav-menu.php 153
$class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args, $depth ) );

Where the hook is used (in WP core)

Usage not found!