wordpress搜索自定义字段

在functions.php中添加

// 搜索自定义字段
function custom_meta_search($search, $query){
    global $wpdb;
 
    if ($query->is_main_query() && !empty($query->query['s'])) {
 
        $sql    = " OR EXISTS (SELECT * FROM {$wpdb->postmeta} WHERE post_id={$wpdb->posts}.ID and meta_key = 'xiaoxian' and meta_value like %s)";
        $like   = '%' . $wpdb->esc_like($query->query['s']) . '%';
        $search .= $wpdb->prepare($sql, $like);
    }
    return $search;
}
add_action('posts_search', 'custom_meta_search',2,2);

注: meta_key = 'xiaoxian'中的xiaoxian根据自己的自定义字段修改