IVBUndoUnit.UnitTypeLong Property (Visio)
Identifies an undo unit by a Long . Read-only.
expression A variable that represents a 'IVBUndoUnit' object.
If you are creating an undo unit for your solution, the UnitTypeLong property is one of the members of IVBUndoUnit that you must implement. You can use the UnitTypeLong value to identify your undo units.
The UnitTypeLong value is optional, and you can and set the value to zero (0) when you implement the property.
For more information about the UnitTypeLong property and using the IVBUndoUnit interface to create undo units, search for "creating undo units" on MSDN, the Microsoft Developer Network.