Autofac resolve IEnumerable<TComponent>仅用于实例化的项

Question

autofac是否为我提供了一种获取元件的所有“活动”实例的方法？这样就可以实现以下功能：

public class ViewManager {

    public ViewManager(Func<IEnumerable<MyView>> viewProvider, Func<string, MyView> viewFactory) {
        ViewProvider = viewProvider;
        ViewFactory = viewFactory;
    }

    public Func<IEnumerable<MyView>> ViewProvider { get; private set; }
    public Func<string, MyView> ViewFactory { get; private set; }

    public MyView GetView(string viewId) {
        var existing = from view in ViewProvider() //this would get me all the active views (not the available implementations)
                       where !view.IsDisposed
                             && view.Id == viewId
                       select view;
        return existing.FirstOrDefault() ?? ViewFactory(viewId);
    }
}

public class MyView: IDisposable {
    public MyView(string id) {
        Id = id;
    }
    public string Id { get; private set; }
    public bool IsDisposed { get; private set; }
    public void Dispose() {
        IsDisposed = true;
    }
}

Answer 1

恐怕不是开箱即用的--对于这种情况，您需要想出另一个方案。您可以使用OnActivated()和OnRelease()事件来保存您自己的活动视图注册表：

builder.RegisterType<ViewRegistry>()
  .As<IViewRegistry>()
  .SingleInstance();

builder.RegisterType<MyView>()
  .OnActivated(e =>
     e.Context.Resolve<IViewRegistry>().Add(e.Instance))
  .OnRelease(e => {
     e.Instance.Dispose();
     e.Context.Resolve<IViewRegistry>().Remove(e.Instance))
  });