【转】[C#] WPF 使用 MVVM 的关闭窗体实现

转自：https://www.codenong.com/23613694

我在使用 WPF + Prism 写一个关闭窗体时，发现 MVVM 不太好使，查到码农家园里这个解决方案确实有效：

<Window ...
        xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity">
<i:Interaction.Triggers>
  <i:EventTrigger EventName="Closing">
    <command:EventToCommand Command="{Binding ClosingCommand}"
                            PassEventArgsToCommand="True" />
  </i:EventTrigger>
</i:Interaction.Triggers>

然后在 VM 中这样：

public RelayCommand<CancelEventArgs> ClosingCommand { get; private set; }

ctor() {
  ClosingCommand = new RelayCommand<CancelEventArgs>(args => args.Cancel = true);
}

要使用Behavior 执行此操作，您可以使用 Behavior ，例如：

internal class CancelCloseWindowBehavior : Behavior<Window> {
  public static readonly DependencyProperty CancelCloseProperty =
    DependencyProperty.Register("CancelClose", typeof(bool),
      typeof(CancelCloseWindowBehavior), new FrameworkPropertyMetadata(false));

  public bool CancelClose {
    get { return (bool) GetValue(CancelCloseProperty); }
    set { SetValue(CancelCloseProperty, value); }
  }

  protected override void OnAttached() {
    AssociatedObject.Closing += (sender, args) => args.Cancel = CancelClose;
  }
}

<i:Interaction.Behaviors>
  <local:CancelCloseWindowBehavior CancelClose="{Binding CancelClose}" />
</i:Interaction.Behaviors>