wordpress标题SEO优化代码：文章标题 – 分类 | 站名

如果你的文章存在多个分类，且希望更精准 SEO，可拼接多个分类或使用主分类：
例：搜索页与文章页的写法，请在functions.php内加入

add_filter('document_title_parts', function($title) {
    if (is_search()) {
        $keyword = get_search_query();
        $title['title'] = '搜索：' . esc_html($keyword);
    } elseif (is_single()) {
        global $post;
        if ($post && has_category('', $post)) {
            $cats = get_the_category($post->ID);
            if (!empty($cats)) {
                if (!empty($title['title'])) {
                    $title['title'] .= ' - ' . $cats[0]->name;
                } else {
                    $title['title'] = $cats[0]->name;
                }
            }
        }
    }
    return $title;
});

在网站首页、标签页、作者页也加入类似 SEO 格式：

add_filter('document_title_parts', function($title) {
    global $post;

    // 获取站点名
    $site_name = get_bloginfo('name');
    $site_desc = get_bloginfo('description');

    if (is_front_page() || is_home()) {
        $title['title'] = $site_name;
        $title['tagline'] = $site_desc;
    } elseif (is_single()) {
        $cats = get_the_category($post->ID ?? 0);
        if (!empty($cats)) {
            $title['title'] .= ' - ' . $cats[0]->name;
        }
        $title['site'] = $site_name;
    } elseif (is_page()) {
        $title['site'] = $site_name;
    } elseif (is_search()) {
        $keyword = get_search_query();
        $title['title'] = '搜索：' . esc_html($keyword);
        $title['site'] = $site_name;
    } elseif (is_category()) {
        $title['title'] = single_cat_title('', false);
        $title['site'] = $site_name;
    } elseif (is_tag()) {
        $title['title'] = '标签：' . single_tag_title('', false);
        $title['site'] = $site_name;
    } elseif (is_author()) {
        $author = get_queried_object();
        $title['title'] = '作者：' . ($author->display_name ?? '未知作者');
        $title['site'] = $site_name;
    } elseif (is_404()) {
        $title['title'] = '页面未找到';
        $title['site'] = $site_name;
    }

    // 如果是分页页，追加页码信息
    if (get_query_var('paged') > 1) {
        $title['title'] .= ' - 第 ' . get_query_var('paged') . ' 页';
    }

    return $title;
});