【列表8.8】修改后的ShutDown 和 SoftShutDown 過程。
{
  The HelpManager calls SoftShutDown to shut down all visible portions
  of the Viewer without actually shutting down the Viewer.
}
procedure TSimpleHelpViewer.SoftShutDown;
begin
   frmTOC.ShutDown;
   frmHelpTopic. ShutDown;
end;
{
   The HelpManager calls ShutDown to shut down the Viewer.
   Since the HelpManager ordered the Viewer to shut down, we don't need
   to notify it.
}
procedure TSimpleHelpViewer.ShutDown;
begin
   SoftShutDown;
   if Assigned(FHelpManager) then
      FHelpManager := nil;
end;