使用Code First和多个继承级别 [英] Using Code First with Multiple Inheritance Levels

问题描述

是否可以使用Code First设置多级继承模型？

假设我有以下类：

LiabilityRate和PropertyRate都继承了具有TPT模型的Rate。

但是我有了
BuildingRate和ContentsRate继承自PropertyRate并带有TPH模型地点，基于名为RateType的PropertyRate表上的列进行区分。

 

这个想法在我脑海里起作用，我就是不能似乎让它与Code First一起工作没有错误。  我的课程如下所示：

 

 
  public   abstract  < span style ="color：Blue;"> class 评分
 {
 [Key] 
  public   int  ID { get ;  set ; } 
 
  public  DateTime EffectiveDate { get ;  set ; } 
  public  DateTime？ EndDate { get ;  set ; } 
} 
 
  public   class  PropertyRate：Rate 
 {
  public   int  TerritoryID {获得;  set ; } 
  public   int  ProgramID {获得;  set ; } 
} 
 
  public   class  LiabilityRate：Rate 
 {
  public   int  TerritoryID {获得;  set ; } 
} 
 
  public   class  BuildingRate：PropertyRate 
 {
  public   decimal  Frame14 {获得;  set ; } 
  public   decimal  Frame58 {获得;  set ; } 
} 
 
  public   class  ContentsRate：PropertyRate 
 {
  public   decimal  Frame14 {获得;  set ; } 
  public   decimal  Frame58 {获得;  set ; } 
} 
 

解决方案

嗨杰夫，

CTP5在混合映射方案中有很多错误，所以它确实不起作用。然而，我们将很快发布一个候选版本，它在混合映射方面更加稳定，并支持这种情况。

有关即将发布的版本的信息在这里;  http：// blogs .msdn.com / b / adonet / archive / 2011/03/02 / ef-4-1-is-coming-dbcontext-api-amp-code-first-rtw.aspx

〜罗文

Is it possible to have a multi-level inheritance model set up with Code First?

Say I have the following classes:

LiabilityRate and PropertyRate both inheriting from Rate with a TPT Model in place.

But then I have
BuildingRate and ContentsRate inheriting from PropertyRate with a TPH Model in place, discriminated based on a column on the PropertyRate table called RateType.

 

The idea works in my head, I just can't seem to get it to work with Code First without errors.  My classes look like this:

 

  public abstract class Rate
  {
    [Key]
    public int ID { get; set; }

    public DateTime EffectiveDate { get; set; }
    public DateTime? EndDate { get; set; }
  }

  public class PropertyRate : Rate
  {
    public int TerritoryID { get; set; }
    public int ProgramID { get; set; }
  }

  public class LiabilityRate : Rate
  {
    public int TerritoryID { get; set; }
  }

  public class BuildingRate : PropertyRate
  {
    public decimal Frame14 { get; set; }
    public decimal Frame58 { get; set; }
  }

  public class ContentsRate : PropertyRate
  {
    public decimal Frame14 { get; set; }
    public decimal Frame58 { get; set; }
  }

解决方案

Hi Jeff,

CTP5 has a lot of bugs around hybrid mapping scenarios, so it really doesn't work. However we will shortly be releasing a Release Candidate which is a lot more stable around hybrid mapping and does support this scenario.

Info about the upcoming releases is here; http://blogs.msdn.com/b/adonet/archive/2011/03/02/ef-4-1-is-coming-dbcontext-api-amp-code-first-rtw.aspx

~Rowan

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