让我们有一个按钮Command绑定到自定义命令属性。
当我应该实现ICommand并从获得时RoutedCommand ？ 我看到的RoutedCommand实现ICommand的 。
在这种情况下，我可能需要iplement一个ICommand ？ 什么MVVM模型？ 哪一个适合用于此目的的更好吗？
Answer 1:
As you have noticed the RoutedCommand class is an implementation of the ICommand interface, its main distinction if that its function is similar to that of a RoutedEvent:
The Execute and CanExecute methods on a RoutedCommand do not contain the application logic for the command as is the case with a typical ICommand, but rather, these methods raise events that traverse the element tree looking for an object with a CommandBinding. The event handlers attached to the CommandBinding contain the command logic.
The Execute method raises the PreviewExecuted and Executed events. The CanExecute method raises the PreviewCanExecute and CanExecute events.
In a case when you don't want the behavior of the RoutedCommand you'll be looking at your own implementation of ICommand. As for the MVVM pattern I can't say that one solution, it seems that everyone has their own methodology. However, here are a few approaches to this problem that I've come across:
- Using RoutedCommands with a ViewModel in WPF
- Relaying Command Logic
- Simple Command (almost identical to Relay Command but worth reading)
Answer 2:
我想补充到丰富的麦圭尔的回答的唯一的事情就是RoutedCommands（和他们的更普遍的后裔RoutedUICommand必须连线了事件处理程序才能正常工作。
大多数MVVM实现我所遇到试图利用对视图模型绑定，因此视图模型（而不是视图）拥有CanExecute /执行逻辑。
相比之下，事件处理程序动议负担的视角。 然后处理可以传播到视图模型，但这意味着一个稍高程度视图模型和视图（铸造+方法调用等）之间的耦合。
文章来源: WPF ICommand vs RoutedCommand
