public MainPageViewModel(INavigationService navigationService, IWhoAreYou iWhoAreYou)
 {
     _IWhoAreYou        = iWhoAreYou;
     _navigationService = navigationService;
     顯示New1PageCommand  = new DelegateCommand(顯示New1Page);
     你是誰Command         = new DelegateCommand(你是誰);
 }
        public MainPageViewModel(INavigationService navigationService,
                                 IPageDialogService dialogService, IWhoAreYou iWhoAreYou,
                                 IEventAggregator eventAggregator)
        {
            _eventAggregator   = eventAggregator;
            _IWhoAreYou        = iWhoAreYou;
            _dialogService     = dialogService;
            _navigationService = navigationService;
            顯示New1PageCommand  = new DelegateCommand(顯示New1Page);
            深層連結Command        = new DelegateCommand(深層連結);
            顯示對話窗Command       = new DelegateCommand(顯示對話窗);
            你是誰Command         = new DelegateCommand(你是誰);

            _eventAggregator.GetEvent <EchoMessage>().Subscribe(EchoDeletage);
        }