ObservableCollection 优于 ObjectSet [英] ObservableCollection better than ObjectSet

问题描述

为什么(在 WPF、C#、实体框架中)将 ListBox 绑定到基于 ObjectSet 创建的 ObservableCollection(来自 EntityFramework)而不是直接绑定到ObjectSet?

Why is it better (in WPF, C#, Entity Framework) to bind ListBox to an ObservableCollection created upon the ObjectSet (from Entity Framework) rather than binding to ObjectSet directly?

还有一个问题:当我将 ListBox 绑定到 ObservableCollection 时，对集合的任何添加都会更新 ListBox.伟大的.但是 ObservableCollection 是在 ObjectContext(在实体框架中)上创建的，并且向集合中添加新项目不会将项目添加到上下文中......如何解决这个问题????

One more question: When I bind ListBox to ObservableCollection, any additions to the collection updates ListBox. Great. But ObservableCollection was created upon ObjectContext (in Entity Framework) and adding a new item to the collection doesn't add the item to the context... how to solve this????

推荐答案

ObservableCollection 实现了 INotifyPropertyChanged 以及 INotifyCollectionChanged，WPF 使用这两种方法将元素重新绑定到 UI.因此，您可以向 ObservableCollection 添加一个项目，并且 UI 会立即更新，而无需您进行代码交互.ObjectSet 两者都没有实现，因此没有获得此功能.

ObservableCollection implements INotifyPropertyChanged as well as INotifyCollectionChanged, both of which WPF uses to rebind elements to the UI. Thus, you could add an item to the ObservableCollection and immediately the UI would update with no code interaction from you. ObjectSet implements neither, and so doesnt get this functionality.

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