You can create a range of objects, from simple lines and circles to spline curves, ellipses, and associative hatch areas. In general, you add objects to a BlockTableRecord object using the AppendEntity function. Once an object is created, you can change its properties such as layer, color, and linetype.
用户可以创建的对象的范围，从简单的直线、圆到复杂的样条曲线、椭圆和关联填充区域。通常，用户使用 AppendEntity 函数添加对象到中一个 BlockTableRecord 对象中。对象创建后，就可以修改对象的像图层、颜色和线型之类的属性。
The drawing database is similar to other database programs, you can think of a Line object in Model space as table record and Model space as its database table. When working with a database, you must open and close records before working with them. The objects stored in the Database object are no different, you use the GetObject function to retrieve an object from the database and define how you want to work with the object.
图形数据库与其它数据库程序相似，可以认为在模型空间中的一个直线对象就相当于一条表记录，模型空间就相当于数据为表。在使用数据库时，必须在使用它们之前打开和关闭记录。与存储在数据库中的对象不同的是，需要使用 GetObject 函数从数据库中获取对象，然后定义你想怎样使用对象。
