The content of any layout is distributed among two different objects: a Layout and BlockTableRecord object. The Layout object contains the plot settings and the visual properties of the layout as it appears in the AutoCAD user interface. The BlockTableRecord object contains the geometry that is displayed on the layout such as annotation, floating viewports, and title blocks. The BlockTableRecord object also includes the Viewport object that controls the display of the drafting aids and layer properties used for the layout.
任何布局的内容都分布在两种不同的对象中：Layout 对象和 BlockTableRecord 对象。Layout 对象包含布局显示在 AutoCAD 用户界面中时的打印设置和视觉特性。BlockTableRecord 对象包含显示在布局中的几何图形，像注释，浮动视口和工程图明细表。BlockTableRecord 对象也包含控制草图辅助的显示的视口对象和已用于布局的图层属性。
Each Layout object is associated with one, and only one, BlockTableRecord object. To access the BlockTableRecord object associated with a given layout, use the BlockTableRecordId property. Conversely, each BlockTableRecord object is associated with one, and only one, Layout object. To access the Layout object associated with a given BlockTableRecord, use the LayoutId property for that block. The IsLayout property of a BlockTableRecord can be used to determine if it has an associated Layout object; TRUE is returned if the BlockTableRecord is associated with a Layout object
每个 Layout 对象与一个并且只能与一个 BlockTableRecord 对象关联。要访问与给定布局关联的 BlockTableRecord 对象，请使用 BlockTableRecordId 特性。与此相对，每个 BlockTableRecord 对象与一个并且只能与一个 Layout 对象关联。要访问与给定 BlockTableRecord 关联的 Layout 对象，请使用该块的 LayoutId 特性。 BlockTableRecord 的 IsLayout 属性可以用于确定是否有一个 Layout 对象与其相关联；如果 BlockTableRecord 和一个 Layout 对象相关联就返回 TRUE。
