The Refresh method forces the control to redraw the
virtual display. Normally, the virtual display is automatically
redrawn after the display has been modified and there are no other
events being processed. However, there may be situations where you
want the display updated immediately.
To prevent the control from automatically redrawing when the
virtual display has been modified, set the AutoRefresh
property to False. You can then call the Refresh method to
force the control to be redrawn as needed.