This method updates the controls that are in the update region.
HRESULT Update( void );
NOERROR indicates success. If an error occurs, the appropriate HRESULT value is returned.
To force a redraw of one control, the IASControl::Redraw method is more efficient because it does not have to search for outdated portions of the region. IASControl::Redraw completely redraws a region, while IASControl::Update refreshes a region by searching for outdated portions of the region.