Application level events respond to changes in the AutoCAD
application and its environment. These events respond to the
opening, saving, closing and printing of drawings, creation of new
drawings, issuing of AutoCAD commands, loading or unloading of ARX
and LISP applications, changes to system variables, and changes to
the Application window.
Document level events respond to the changes of a specific
document or its contents. These events respond to the addition,
deletion, or modification of objects, activation of a shortcut
menu, changes in the pickfirst selection set, changes to the
Drawing window, and regeneration of the drawing. There are also
document level events for the opening, closing, and printing of a
drawing, and the loading or unloading of ARX and LISP applications
from the drawing.
Object level events respond to the changes of a specific
object. Currently there is only one object level event. It is
triggered whenever an object is modified.
that respond to events are called event
handlers and are executed automatically each and every time
their designated event is triggered. Information contained in
events, such as the drawing name in the BeginOpen event, are passed
to event handlers through parameters.