WordPress本地环境自定义插件无法获取当前页面ID求助

问题情况 #

在自定义WordPress插件中尝试获取当前页面ID时，始终返回null或false。打印$wp_query的结果显示in_the_loop为false，所有页面相关属性均为空：

/srv/www/wordpress/wp-content/plugins/blueprint/partials/helpers.php:5:
object(WP_Query)[553]
  public 'query' => null
  public 'query_vars' => 
    array (size=0)
      empty
  public 'tax_query' => null
  public 'meta_query' => boolean false
  public 'date_query' => boolean false
  public 'queried_object' => null
  public 'queried_object_id' => null
  public 'request' => null
  public 'posts' => null
  public 'post_count' => int 0
  public 'current_post' => int -1
  public 'in_the_loop' => boolean false
  public 'post' => null
  public 'comments' => null
  public 'comment_count' => int 0
  public 'current_comment' => int -1
  public 'comment' => null
  public 'found_posts' => int 0
  public 'max_num_pages' => int 0
  public 'max_num_comment_pages' => int 0
  public 'is_single' => boolean false
  public 'is_preview' => boolean false
  public 'is_page' => boolean false
  public 'is_archive' => boolean false
  public 'is_date' => boolean false
  public 'is_year' => boolean false
  public 'is_month' => boolean false
  public 'is_day' => boolean false
  public 'is_time' => boolean false
  public 'is_author' => boolean false
  public 'is_category' => boolean false
  public 'is_tag' => boolean false
  public 'is_tax' => boolean false
  public 'is_search' => boolean false
  public 'is_feed' => boolean false
  public 'is_comment_feed' => boolean false
  public 'is_trackback' => boolean false
  public 'is_home' => boolean false
  public 'is_privacy_policy' => boolean false
  public 'is_404' => boolean false
  public 'is_embed' => boolean false
  public 'is_paged' => boolean false
  public 'is_admin' => boolean false
  public 'is_attachment' => boolean false
  public 'is_singular' => boolean false
  public 'is_robots' => boolean false
  public 'is_favicon' => boolean false
  public 'is_posts_page' => boolean false
  public 'is_post_type_archive' => boolean false
  private 'query_vars_hash' => boolean false
  private 'query_vars_changed' => boolean true
  public 'thumbnails_cached' => boolean false
  private 'stopwords' => null
  private 'compat_fields' => 
    array (size=2)
      0 => string 'query_vars_hash' (length=15)
      1 => string 'query_vars_changed' (length=18)
  private 'compat_methods' => 
    array (size=2)
      0 => string 'init_query_flags' (length=16)
      1 => string 'parse_tax_query' (length=15)

当前使用的代码是：

<?php
add_action('init','newFunction');
function newFunction(){
  global $wp_query;
 var_dump($wp_query);
 // Do your code here
}

核心需求是获取当前页面ID，判断是否在指定ID列表中，从而决定是否渲染插件内容。

问题原因 #

init钩子触发时机过早，此时WordPress还未完成主查询的初始化，$wp_query对象还未填充页面相关数据，自然无法获取到页面ID。

解决方案 #

1. 替换为合适的钩子 #

选择在主查询完成后触发的钩子，比如wp或template_redirect：

<?php
// 使用wp钩子
add_action('wp', 'newFunction');
function newFunction(){
    $page_id = get_queried_object_id();
    // 检查页面ID是否在列表中
    $target_pages = [1, 2, 3]; // 替换为你的页面ID列表
    if (in_array($page_id, $target_pages)) {
        // 渲染插件内容
        echo '插件内容';
    }
}

或者使用template_redirect钩子：

<?php
add_action('template_redirect', 'newFunction');
function newFunction(){
    global $post;
    if ($post) {
        $page_id = $post->ID;
        $target_pages = [1, 2, 3];
        if (in_array($page_id, $target_pages)) {
            // 执行渲染逻辑
        }
    }
}

2. 直接使用get_queried_object_id()函数 #

该函数无需依赖全局变量，可直接返回当前查询对象的ID，在主查询完成后调用即可：

$page_id = get_queried_object_id();
if ($page_id && in_array($page_id, $target_pages)) {
    // 执行插件渲染操作
}

3. 后台页面的ID判断（如果需要） #

如果要在WordPress后台判断页面ID，可结合get_current_screen()函数：

add_action('admin_init', 'check_admin_page');
function check_admin_page(){
    $screen = get_current_screen();
    if ($screen && $screen->base === 'post' && $screen->post_type === 'page') {
        $page_id = $_GET['post'] ?? 0;
        $target_pages = [1,2,3];
        if (in_array($page_id, $target_pages)) {
            // 后台相关逻辑
        }
    }
}

内容的提问来源于stack exchange，提问作者Muhammad Fahad