// Assign Unique Classes To First And Last Menu Items
function first_last_class( $items ) {
	$position = strrpos($items, 'class="menu-item', -1);
	$items=substr_replace($items, 'menu-item-last ', $position+7, 0);
	$position = strpos($items, 'class="menu-item');
	$items=substr_replace($items, 'menu-item-first ', $position+7, 0);
	return $items;
}
add_filter( 'wp_nav_menu_items', 'first_last_class' );

Use this function to filter your first and last menu items and assign them each a specific class name. This is very handy when applying separators in CSS but want to exclude the first and/or last items.

Assign Unique Classes To First And Last Menu Items

wordpress

PHP