Can you explain how the MergeUndoRecords method is suppossed to work?

I have a function that allows a user to take a long branch and split it at a certain node into a couple of branches. This function makes many changes to the diagram including creating new boxes, creating new arrows, deleting existing arrows, and creating/destroying groups.

I want the user to be able to undo the entire process if they need to. The way I'm currently doing this is like this:

• I set a long(lUnCnt) to 0 at the beginning of the function
• In the UndoActionRecorded event, I increment the long each time that event is fired.
• Before any manipulation starts, I call fc.BeginUndoRecord
• When the manipulation is complete, I call fc.EndUndoRecord
• I then call fc.MergeUndoRecords lUnCnt

After the process is complete, If I call fc.Undo, it seems to have no effect.

Am I doing something wrong?

*NOTE* fc.UndoDepth is set to 10000 (Usually only ever hit about 3500 undo records during this process). Also, if I call fc.Undo within this function after all of the above, it sucessfully Undoes everything. However, I need the user to make that determination AFTER the manipulation is complete and the function has ended.


Thanks,
Alan

Ok, it works now.

There was an un-handled error in my GroupDestroyed event that was happening when the undo was issued that basically caused the Undo operation to abort.

Thanks,
Alan