是的，我认为应该可以通过编程方式添加和删除nav菜单项。您可以使用wp_nav_menu_objects 或wp_nav_menu_items 筛选以编辑导航菜单。或者如果您可以编辑menu walker, 您可以在其中添加事件项。

使用您可以使用的第一个过滤器wp_update_nav_menu_item 创建新菜单项并将其保存到数据库。您应该能够使用删除菜单项wp_delete_post. 对于后者，您将处理nav菜单的html，因此您可以将html字符串附加到菜单中。

如果事件日期存储为post meta，则可以使用custom field WP_Query 获取具有未来日期的事件。

下面是一个非常粗略的示例wp_nav_menu_objects 这是我根据法典和代码参考而想到的。希望您可以将此作为创建工作解决方案的起点<这绝不是一个有效的代码示例，需要调整、微调，也许还需要一些排版

add_filter( \'wp_nav_menu_objects\', \'prefix_wp_nav_menu_objects\', 10, 2 );
function prefix_wp_nav_menu_objects( $menu_items, $args ) {
  // Check if correct menu  
  if ( \'my-theme-location\' === $args[\'theme_location\'] ) {
    // Loop items
    $time_now = time();
    foreach ( $menu_items as $key => $menu_item ) {
      // Add new items to correct submenu
      if ( $add_item_logic === $menu_item->property_to_compare ) { // add applicable logic
        $new_items = prefix_add_items_menu( $menu_item, $args );
        $menu_items = $menu_items + $new_items; // add new items to the menu item array
      } else if ( $remove_item_logic === $menu_item->property_to_compare ) { // add applicable logic
        $event_date = get_post_meta( $menu_item->db_id, \'event_date\', true );
        if ( $event_date && strtotime( $event_date ) < $time_now ) {
          // Delete menu item permanently
          wp_delete_post( $menu_item->db_id ); // check if property is correct
          // Remove from menu item array
          unset( $menu_items[$key] );
        }
      }      
    }

  }

  return $menu_items;
}

function prefix_add_items_menu( $menu_item, $menu_args ) {
  $new_items = array();

  $query_args = array(
    \'post_type\'      => \'my_cpt_slug\', // add correct cpt slug
    \'posts_per_page\' => 10, // adjust as needed
    \'meta_key\'       => \'event_date\', // add correct meta key if date saved in post meta
    \'meta_value\'     => date( "Ymd" ), // change to how "event date" is stored
    \'meta_compare\'   => \'>=\' // change comparison methof if needed
  );
  $query = new WP_Query( $query_args );

  if ( $query->posts ) {

    foreach ( $query->posts as $event ) {

      // If you want to create menu items          
      wp_update_nav_menu_item( $menu_args[\'menu_id\'], 0, array(
        \'menu-item-title\'     => $event->post_title,
        \'menu-item-object-id\' => $event->ID,
        \'menu-item-object\'    => $event->post_type,
        \'menu-item-parent-id\' => $menu_item->ID, // not sure if property is correct, please check it yourself
      ));

      // And / or push posts to menu items
      $new_items[] = array(
        \'menu-item-title\'     => $event->post_title,
        \'menu-item-object-id\' => $event->ID,
        \'menu-item-object\'    => $event->post_type,
        \'menu-item-parent-id\' => $menu_item->ID, // not sure if property is correct, please check it yourself
      );

    }    
  }

  return $new_items;
}

您还可以查看相关的WPSE Q&；A关于这件事，

Add items to a menu dynamically

Programmatically add a Navigation menu and menu items

Add items to a menu dynamically

Remove a menu item in menu

EDIT 1实际上，您可以在上更新菜单save_post, 发布新事件时也是如此。这可能是更好的方式来更新菜单，因为我现在想得更多。发布新帖子时进行更新意味着更新功能的运行频率较低，从而降低了网站的总体负担。

要从菜单中删除过去的事件，可以考虑添加一个每天运行一次的自定义wp cront事件。

function prefix_update_menu( $post_id, $post ) {
  // New post only
  if ( $post->post_date !== $post->post_modified ) {
    return;
  }
  // Get main menu items
  $main_menu_items = wp_get_nav_menu_items( \'menu-id-slug-name-or-object\' );
  if ( ! $main_menu_items ) {
    return;
  }

  // 1. foreach Loop menu items
  // 2. when correct submenu is matched add new menu item with wp_update_nav_menu_item
  // 3. optionally also remove passed events while doing the foreach loop
  // get post id from menu item with get_post_meta( $item->ID, \'_menu_item_object_id\', true );
  // then get event end date and current date for comparison
  // remove menu item with delete_postw p_delete_post( $item->ID );

}
add_action( \'save_post\', \'prefix_update_menu\', 10, 2 );