XAF 一对多关系<DC翻译博客二>

DC: 一对多关系
In the first post of the series devoted to our new domain component (DC) technology, I tried to show an interface-defined entity in a UI.

在第一篇博客专门讨论我们新的领域构件技术，我试着在界面显示一个接口定义实体。

I used some IPerson component as an example:
我用一些Iperson构件作为例子：

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1	public enum Gender { Unknown, Male, Female }
2
3	public interface IPerson {
4	string FirstName { get; set; }
5	string MiddleName { get; set; }
6	string LastName { get; set; }
7	string FullName { get; }
8	DateTime Birthday { get; set; }
9	Gender Gender { get; set; }
10	}
11	[DomainLogic(typeof(IPerson))]
12	public class PersonLogic {
13	public static string Get_FullName(IPerson self) {
14	return self.FirstName + " " + self.LastName;
15	}
16	}

IPerson is a library interface that will be used as an entity rarely. In a real-world application, another entity is expected. For instance, it may be a Developer, the entity that implements the IPerson interface, in addition to other interfaces. Assume the Developer contains Notes. So, we add the INote and IItemWithNotes library interfaces:
Iperson是一个库接口，很少最为实体用。在现实世界的应用程序，另一实体是被预期的。例如，他可能是一个开发者，实体实现Iperson接口，除了其他接口。认为开发包括备注。因此，我们添加Inote和IitemWithNote库接口：

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1	public interface IItemWithNotes {
2	IList<INote> Notes { get; }
3	}
4
5	public interface INote {
6	string Text { get; set; }
7	IItemWithNotes Owner { get; set; }
8	}

Combining these two interfaces, we get the IDeveloper interface:

结合这两个接口，我们得到了Ideveloper接口：

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1	public interface IDeveloper : IPerson, IItemWithNotes{
2	}

I change the entity registration code, which I showed in the previous post, to the following:
我更改实体注册代码，我发布在以前的帖子上，如下：

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1	public override void Setup(XafApplication application) {
2	XafTypesInfo.Instance.AddEntityToGenerate("Developer", typeof(IDeveloper));
3	XafTypesInfo.Instance.GenerateEntities();
4	base.Setup(application);
5	}

If I run my application now, it won't work. The problem is that I should map the INote interface to a real entity. Here, I have a design challenge: should XAF generate other entities for the Developer entity, or should it require that all Developer-related entities are registered manually? Currently, I think it is better to make a developer responsible for registering entities. First, it will give him direct control on what happens in the physical database. Second, our automatic logic can be wrong. So, I change the entity registration code again:
如果我现在运行我的应用程序，它不能运行。问题是，·映射一个真实的实体接口。这里，我有了设计挑战：XAF为开发者实体生成其他实体，或者，现在应当需要手动注册所有开发者相关实体，我认为最好的方法是让开发者自己负责注册实体。首先，会给它直接控制在数据库操作。其次，我们的自动逻辑可能是错的。因此，我再次改变实体注册代码：

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1	public override void Setup(XafApplication application) {
2	XafTypesInfo.Instance.AddEntityToGenerate("Developer", typeof(IDeveloper));
3	XafTypesInfo.Instance.AddEntityToGenerate("Note", typeof(INote));
4	XafTypesInfo.Instance.GenerateEntities();
5	base.Setup(application);
6	}

After I made these changes, my application works:
更改之后，应用程序可以运行：

Note that the FullName property is calculated properly. Remember that we declared this property with a getter only. However, we implemented the PersonLogic class that contains the Get_FullName method. When the XpoBuilder generated the implementation of the Developer object, it uses the Get_FullName method to generate the FullName property.
注意，FullName属性是计算属性。记得，我们只用一个getter定义这个属性。然而，我们实现了包含Get_FullName方法的类。当XpoBuilder生成开发者对象的实现时，它用了Get_FullName方法生成FullName属性。

As you can see in the screenshot above, the "Link" and "Unlink" Actions are available (they are circled). This means that the system thinks that a Note object can be created independently. I need a way to tell the XpoBuilder that the
IItemWithNotes.Notes is an aggregated collection. I want to be able to write this:
正如你在上面截图中看到的，“Link”和“Unlink”按钮可用。这就意味系统认为独立创建一个Note对象.我需要一个方法告诉XpoiBuilderIItemWithNotes.Notes是一个聚集集合。我希望是这样写：

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1	public interface IItemWithNotes {
2	[Aggregated]
3	IList<INote> Notes { get; }
4	}

I still can't do that. So, I've written a test that shows what I need, and now I’m waiting for the Xpo team. I'll focus on other problems with associations. Stay tuned.
我仍不能做到这一点。因此，我写一个测试显示我需求什么，现在，我等待XPO团队。我将关注与关联相关的问题。敬请关注。