MEF过滤器导入很多

Question

假设我有以下3个课程：

[Export("Settings",typeof(ISettingsItem)]
[PartCreationPolicy(CreationPolicy.Shared)]
public class Settings1Vm {}

[Export("Settings",typeof(ISettingsItem)]
[PartCreationPolicy(CreationPolicy.Shared)]
public class Settings2Vm {}

[Export("Settings",typeof(ISettingsItem)]
[PartCreationPolicy(CreationPolicy.Shared)]
public class Settings3Vm {}

例如，如果可以这样做：

[Import]
private ISettingsItem SettingEntry{ get; set; }

但是以某种方式这种导入仅采用Settings2VM类的导出？

问候

Answer 1

看来解决方案是：

[Export("Settings",typeof(ISettingsItem)]
[Export("Settings2Vm ",typeof(ISettingsItem)]
[PartCreationPolicy(CreationPolicy.Shared)]
public class Settings2Vm {}

[Import("Settings2Vm ", typeof(ISettingsItemVM))]
private Settings2Vm SettingEntry{ get; set; }

这样，我将始终拥有相同的实例。