使用TextBox容器的KeyDown事件(比如说StackPanel)来监听键盘事件.所以你的代码会像这样工作

private void stackPanel_KeyDown(object sender,KeyRoutedEventArgs e)
    {
        if (e.Key == Windows.System.VirtualKey.Enter)
        {
            if (FocusManager.GetFocusedElement() == inputTextBox) // Change the inputTextBox to your TextBox name
            {
                FocusManager.TryMoveFocus(FocusNavigationDirection.Next);
                FocusManager.TryMoveFocus(FocusNavigationDirection.Next);
            }
            else
            { 
                FocusManager.TryMoveFocus(FocusNavigationDirection.Next);
            }

            // Make sure to set the Handled to true,otherwise the RoutedEvent might fire twice
            e.Handled = true;
        }
    }

有关FocusManager的更多详细信息,请参阅https://msdn.microsoft.com/en-us/library/windows/apps/windows.ui.xaml.input.focusmanager.trymovefocus

有关KeyDown的更多详细信息,请参阅https://msdn.microsoft.com/en-us/library/windows/apps/windows.ui.xaml.uielement.keydown