Javascript problem

My situation is the following :

My page contains a Goview encapsulated in a new control. A printing button launches a javascript treatment. When I arrive on my page, the diagram is saved on the server, but if I changed anything (moving a shape, etc), the modifications are not saved.
So, I would like to know if it's possible in the javascript to save my control as a bitmap, because at this moment, the control knows the changements done.
I'm using
I though about the possibility to use the event onChanged, but it means that the file is writen on the server each time there's a modification, so that's too long.

I’m not sure I understand your situation and problem. But if you want to save your “document” whenever there is a change, and if you do not want to do it each time there is a GoDocument.Changed event (I agree that would almost certainly be too inefficient), then you could do it each time there is a GoDocument.Changed event with a Hint == GoDocument.FinishedTransaction. If you support undo and redo, you can also check for the Hints GoDocument.FinishedUndo and .FinishedRedo.