我有以下功能以选择格式输出一个自定义菜单，用于我正在处理的响应性设计。

它的工作方式正是我想要它除了我需要排除子菜单项。目前，它包括所有级别。

有人知道我怎么说吗wp_get_nav_menu_items是否只显示顶级菜单项？

function jeMobileMenu( $args ) {

        // Set up defaults arguments
        $defaults = array (
            \'menuSlug\'      =>  \'\',
            \'placeholder\'   =>  \'Menu\',
            \'prefix\'        =>  \' » \',
            \'navID\'         =>  \'mobileNav\',
            \'navClass\'      =>  \'\'
        );

        // Parse incomming $args into an array and merge it with $defaults
        $args = wp_parse_args( $args, $defaults );

        //Declare each item in $args as its own variable i.e. $menuSlug, $placeholder
        extract( $args, EXTR_SKIP );

        // If no menu slug has been passed then lets bail
        if ( empty($menuSlug) )
            return;

        // If the menu slug that has been passed doesn\'t correspond to an exisiting menu then lets bail
        if ( !has_nav_menu( $menuSlug ) )
            return;


        $locations = get_nav_menu_locations();
        $menu = wp_get_nav_menu_object( $locations[ $menuSlug ] );

        $menu_items = wp_get_nav_menu_items($menu->term_id);

        // Wrap the select in a nav element with passed id and classes
        $menu_output = \'<nav id="\' . $navID . \'" class="\' . $navClass . \'">\';

        $menu_output .= \'<select id="menu-\' . $menuSlug . \'" onchange="window.open(this.options[this.selectedIndex].value,\\\'_top\\\')">\';

        // Add placeholder and home link
        $menu_output .= \'<option value="">\' . $placeholder . \'</option>\';
        $menu_output .= \'<option value="\' . home_url( \'/\' ) . \'">\' . $prefix . \'Home</option>\';

        // Now loop through all the menu items and create them as options in the select list        
        foreach ( (array) $menu_items as $key => $menu_item ) {
            $title = $menu_item->title;
            $url = $menu_item->url;
            $menu_output .= \'<option value="\' . $url . \'">\' . $prefix . $title . \'</option>\';
        }
        $menu_output .= \'</select>\';

        $menu_output .= \'</nav>\';

        echo $menu_output;
    }