获取用户定义的对象，它限定或包含关于异步操作的信息。
Gets a user-defined object that qualifies or contains information about an asynchronous operation.
导航或修改的数据对象不如使用用户定义的对象包装器时那么明显。
Data object being navigated or modified are not as obvious as they would be with a user-defined object wrapper.
一个应用，它利用用户定义的对象和可定制的文件格式以面向对象的风格存储数据。
An application that utilizes user defined objects and customizable file formats to store data in an object oriented fashion.
应用推荐