What's a custom object?

摘要

Another good reason not to inherit from the existing AutoCAD entity objects is, you are setting up a hierarchy other processes may have trouble following; that is, you are defining a system where there are two objects that are similar at the same level. To AutoCAD and other ARX programs, your custom object would appear as a standard object at first glance. And it may be manipulated as a simple object resulting in the loss of data from any custom properties you were using.