WordPress获取所有分类名称和ID

在function.php添加代码：

/**
 * 获取WordPress所有分类名称和ID
 * https://www.lrmb.net
 */
function show_category(){
    global $wpdb;
    $request = "SELECT $wpdb->terms.term_id, name FROM $wpdb->terms ";
    $request .= " LEFT JOIN $wpdb->term_taxonomy ON $wpdb->term_taxonomy.term_id = $wpdb->terms.term_id ";
    $request .= " WHERE $wpdb->term_taxonomy.taxonomy = 'category' ";
    $request .= " ORDER BY term_id asc";
    $categorys = $wpdb->get_results($request);
    foreach ($categorys as $category) { //调用菜单
        $output = ''.$category->name."(".$category->term_id.')';
        echo $output;
    }
}

在想要输出分类的位置添加如下代码：

<?php show_category(); ?>

分类输出演示效果：