一. wp_users表

检测和更新操作
    $user_name          =   $data['user_name'];
    $user_pass          =   $data['old_passwd'];
    // wp 判断 user表里是否有这个登陆名
    $user               =   get_user_by( 'login',$user_name );  
    //检测密码和修改数据 以user表的ID为原点
    //  wp内置方法 只能检查 wp_users表
    if ($user && wp_check_password($user_pass, $user->data->user_pass, $user->ID)) {
            $user_data = wp_update_user( array( 'ID' => $user->ID, 'user_pass' => $data['new_passwd'] ) );
            // 这里修改密码
            if ( is_wp_error( $user_data ) ) {
                // There was an error; possibly this user doesn't exist.
                $res = array('code' => 1, 'message' => '修改密码失败', 'data' => null);
            } else {
                // Success!
                $res = array('code' => 0, 'message' => '修改成功', 'data' => null);
            }

        } else {
            $res = array('code' => 1, 'message' => '用户密码错误', 'data' => null);
        }