这取决于您所谈论的菜单类型：

1）

使用动作挂钩创建新功能add_category

在该功能中，您可以创建一个新的帖子类型menuitem类型，该类型会正确添加到菜单中

每当发布新类别时，都会立即添加菜单项

您还应该连接到“删除”类别，以使菜单保持最新

如果没有wordpress菜单，您可以做得更简单：

只需编写一个函数来列出您的类别（或使用预定义的wp_list_categories 函数）

我更喜欢使用wp_list_categories. 以下是我在上一个项目中使用的代码：

<?php wp_list_categories(\'orderby=ID&exclude=3,10,1,16,38&title_li=<span class="sidebar_heading d_shadow">\' . __(\'Categories\') . \'</span>\'); ?>

经过多次研究，我找到了一个可靠而有用的解决方案，这门课效果很好：

class EntexAutoSubmenu {

    /**
     * Constructor
     */
    function __construct(){
        add_action(\'created_category\', array($this, \'on_publish_category\'));
    }

    /**
     * When publishing a new child category, add it to the appropriate custom menu.
     */
    function on_publish_category($cat_id){

        // Theme supports custom menus?
        if (!current_theme_supports(\'menus\')) return;

        // Published taxonomy has parent?
        $cat = get_category($cat_id);
        if (!$cat->category_parent) return;

        $all_menus = get_terms(\'nav_menu\', array(\'hide_empty\' => true));

        // Loop through the menus to find page parent
        foreach ($all_menus as $menu) {

            $menu_parent = NULL;
            $menu_items = wp_get_nav_menu_items($menu->term_id, array(\'post_status\' => \'publish,draft\'));

            if (!is_array($menu_items)) continue;

            foreach ($menu_items as $menu_item){
                // Item already in menu?
                if ($menu_item->object_id == $cat_id) continue 2;
                if ($menu_item->object_id == $cat->category_parent) $menu_parent = $menu_item;
            }

            // Add new item
            if ($menu_parent) {
                wp_update_nav_menu_item($menu->term_id, 0, array(
                    \'menu-item-object-id\' => $cat_id,
                    \'menu-item-object\' => $cat->taxonomy,
                    \'menu-item-parent-id\' => $menu_parent->ID,
                    \'menu-item-type\' => \'taxonomy\',
                    \'menu-item-status\' => \'publish\'
                ));
            }
        }
    }
}

$auto_submenu = new EntexAutoSubmenu();

另一种选择是使用List Custom Taxonomy Widget, 它可能适用于您的用例（如果您不打算使用WP nav\\U菜单）。

我为我的一个客户编写了自己的代码

<div class="menu">
  <ul id="MenuBar1" class="MenuBarHorizontal">
    <li><a <?PHP if( count($_GET) == 0 ){ echo \'class="-current"\';} ?> href="<?php echo esc_url( home_url( \'/\' ) ); ?>">home</a></li>
    <?php
        $category_ids = get_all_category_ids();
        sort($category_ids);
        foreach($category_ids as $cat_id) {
            $cat_name = get_cat_name($cat_id);

            echo \'<li><a href="\' . get_category_link( $cat_id ) . \'">\' . $cat_name . \'</a>\';            
            $args = array( \'numberposts\' => -1, \'offset\'=> 0, \'cat\' => $cat_id, \'orderby\' => \'ID\', \'order\' => \'ASCE\' );     

            echo \'<ul>\';

            /* The 2nd Query (without global var) */
            $query2 = new WP_Query( $args );
            // The 2nd Loop
            while( $query2->have_posts() ):
                $query2->next_post();
                echo \'<li><a href="\' . get_permalink( $query2->post->ID ) . \'">\' . get_the_title( $query2->post->ID ) . \'</a></li>\';
            endwhile;

            // Restore original Query & Post Data
            wp_reset_query();
            wp_reset_postdata();
            echo \'</ul>\';
        echo \'</li>\';
        }
    ?>
  </ul>
</div>

为了解决这个问题，我尝试创建一个插件，如果在菜单中，它会自动为父类别下的发布类别创建菜单项。

插件理念：

1.在代码中，我使用"created_$taxonomy" 行动挂钩。

2.收集所有菜单项（使用wp_get_nav_menu_items）

3.如果发布类别的父级位于菜单项中，而不是创建为其父类别的子菜单的菜单项中，则放置条件。（通过使用wp_update_nav_menu_item)

<?php
/*
Plugin Name: Auto Category Submenu
Plugin URI: 
Description: Create menu item when category publish/create if it\'s parent category in menu item.
Version: 0.1
Author: Mayank Gupta/Ravinder Kumar
Author URI: 
License: GPL2
*/

class AutoSubmenu {

    /**
     * Constructor
     */
    function __construct() {
        add_action( \'created_category\', array( &$this, \'on_publish_cat\' ) );
    }

    /**
     * When publishing a new child page, add it to the appropriate custom menu.
     */
    function on_publish_cat( $cat_id ) {
        $cat = get_category( $cat_id );

        //menu id for you menus in which your sub-category\'s parent category as menu item 
        $menu_ids = array(101,100);

        //retrieve all meu items from menu
        foreach($menu_ids as $menu_id){
            $menu_items[] = wp_get_nav_menu_items( $menu_id, array(\'post_status\' => \'publish\',\'post_type\' => \'nav_menu_item\',\'output\' => ARRAY_A, ) );
        }
        foreach($menu_items as $menu_item){
            $counter = 0 ;
            echo\'<!--\';
            print_r($menu_item);
            echo\'-->\';
            foreach($menu_item as $menu_term){
                $menu_terms_id[] = $menu_term->object_id; //all menu items id
            }
        }
        //print_r($menu_terms_id); //test for items in menu
        foreach( $menu_terms_id as $menu_term ){
            if( $cat->category_parent == $menu_term){
                wp_update_nav_menu_item( $cat_id, 0, array(
                \'menu-item-object-id\' => $cat_id,
                \'menu-item-object\' => $cat->taxonomy,
                \'menu-item-parent-id\' => $menu_term,
                \'menu-item-type\' => \'category\',
                \'menu-item-status\' => \'publish\'
            ) );
            }else{
                return;
            }
        }
    }

}
$auto_submenu = new AutoSubmenu();

我正在使用在我的项目中将所有类别和类别的子类别显示为菜单。

$all_categories = get_categories( $args );
echo "<div class=\'container\'>";
 echo "<div class=\'productsubmenu\'>";
echo "<ul>";

foreach ($all_categories as $cat)
{           

if($cat->category_parent == 0)
 {
  $category_id = $cat->term_id;
   $thumbnail_id = get_woocommerce_term_meta( $cat->term_id,    \'thumbnail_id\', true );
$image = wp_get_attachment_url( $thumbnail_id );

echo \'<li class="parent \'.$my.\' "><a href="\'.get_term_link( $cat ) . \'">\'.$cat->name.\'</a>\';


$args2 = array(
\'taxonomy\' => $taxonomy,
\'child_of\' => 0,
\'parent\' => $category_id,
\'orderby\' => $orderby,
\'show_count\' => $show_count,
\'pad_counts\' => $pad_counts,
\'hierarchical\' => $hierarchical,
\'title_li\' => $title,
\'hide_empty\' => $empty

);
   $args = array(
   \'hierarchical\' => 1,
   \'show_option_none\' => \'\',
   \'hide_empty\' => 0,
   \'parent\' => $parent_cat_ID,
   \'taxonomy\' => \'product_cat\'
);
 $subcats = get_categories($args2);
 echo \'<ul class="wooc_sclist">\';

  foreach ($subcats as $sc) { 

        }

    $link = get_term_link( $sc->slug, $sc->taxonomy );
    echo \'<li class="\'.$my.\'" ><a href="\'. $link .\'">\'.$sc->name.\'</a></li>\';
  }
echo \'</ul>\';
echo "</li>";
}
else
{

 }
 }

    echo "</ul>";
   echo "</div>";
   echo "</div>";

这是我的方法，适用于产品类别。

$cat_args = array( \'orderby\' => \'name\', \'order\' => \'asc\', \'hide_empty\' => true,);
$cats = get_terms( \'product_cat\', $cat_args );
foreach ($cats as $key => $cat):
  if ($cat->parent == 0):
    echo $cat->name;
    foreach ($cats as $key => $cat2):
      if ($cat2->parent == $cat->term_id):
        echo $cat2->name;
        foreach ($cats as $key => $cat3):
          if ($cat3->parent == $cat2->term_id):
            echo $cat3->name;
          endif;
        endforeach;
      endif;
    endforeach;
  endif;
endforeach;