Number of items to undo in Visio Drawing Control 2003

[Marx]

Hello,

Is there a property that indicates how many items there are to undo? Or if
there are any items on the undo stack?

 

[JuneTheSecond]

How would you mind to create undo unit.
http://msdn2.microsoft.com/en-us/library/aa201808(office.10).aspx

 

[Marx]

I think the undoUnit has a different purpose:
"It contains the actions needed to undo or redo changes to an external data
source that reflect changes in the drawing."

Thanks for the reply.