NotSupportedException：类型A无法映射为定义。混凝土表（TPC）EF6 [英] NotSupportedException: The type A cannot be mapped as definede. Table per Concrete (TPC) EF6

问题描述

  public abstract class Entity 
 {
 public int Id {get ;组; 
 
 
 public abstract class Tree：Entity 
 {
 public Tree（）{Childs = new List< Tree>（）; } 
 
 public int？ ParentId {get;组; } 
 
 public string Name {get;组; } 
 
 [ForeignKey（ParentId）] 
 public ICollection< Tree>孩子{get;组; 
 
} 
 
 public abstract class Cat：Tree 
 {
 
 public string ImageUrl {get;组; } 
 
 public string描述{get;组; } 
 
 public int OrderId {get;组; 
 
} 
 
 public class ItemCat：Cat 
 {
 ... 
 public virtual ICollection< Item>物品{get;组; 
} 
  

和配置类：

  public class CatConfig：EntityTypeConfiguration< Cat> 
 {
 public CatConfig（）
 {
 //属性
属性（rs => rs.Name）.IsUnicode（）; 
属性（rs => rs.ImageUrl）.IsUnicode（）; 
属性（rs => rs.Description）.IsUnicode（）; 
} 
} 
 
 public class ItemCatConfig：EntityTypeConfiguration< ItemCat> 
 {
 public ItemCatConfig（）
 {
 
 Map（m => {m.ToTable（ItemCats）; m.MapInheritedProperties（）;}） ; 
} 
} 
  

和DbContext：

  public class Db：IdentityDbContext< MehaUser> 
 {
 public Db（）：base（Db）
 {
} 
 
 public DbSet< ItemCat> ItemCats {get;组; 
} 
 protected override void OnModelCreating（DbModelBuilder mb）
 {
 mb.Configurations.Add（new ItemCatConfig（））; 
 
 base.OnModelCreating（mb）; 
} 
  

但获取：

< blockquote>

System.NotSupportedException：类型ItemCat无法按照定义进行映射，因为它将继承的属性从使用实体分割或其他形式继承的类型映射。选择不同的继承映射策略，以便不映射继承的属性，或者更改层次结构中的所有类型以映射继承的属性并且不使用拆分。

更新：我也阅读此

解决方案

找到答案。只需删除ItemCatConfig类中的 Map 。

  Map（m => {m.ToTable（ ItemCats）; m.MapInheritedProperties（）;}）; 
  

在TPC中，抽象类不会在数据库中实现。
ItemCat从抽象类继承，并且不需要显式映射配置。

I have model like:

public abstract class Entity   
 {    
    public int Id { get; set; }  
  }

public abstract  class Tree : Entity
    {
        public Tree() { Childs = new List<Tree>(); }

        public int? ParentId { get; set; }

        public string Name { get; set; }

        [ForeignKey("ParentId")]
        public ICollection<Tree> Childs { get; set; }

    }

 public  abstract class Cat : Tree
    {

        public string ImageUrl { get; set; }

        public string Description { get; set; }

        public int OrderId { get; set; }

    }

  public class ItemCat : Cat
        {
            ...
            public virtual ICollection<Item> Items { get; set; }
        }

and config classes:

public class CatConfig : EntityTypeConfiguration<Cat>
    {
        public CatConfig()
        {
            //properties
            Property(rs => rs.Name).IsUnicode();
            Property(rs => rs.ImageUrl).IsUnicode();
            Property(rs => rs.Description).IsUnicode();
        }
    }

 public class ItemCatConfig :EntityTypeConfiguration<ItemCat>
    {
        public ItemCatConfig()
        {

            Map(m => { m.ToTable("ItemCats"); m.MapInheritedProperties(); });
        }
    }

and DbContext:

public class Db :  IdentityDbContext<MehaUser>
    {
        public Db():base("Db")
        {
        }

        public DbSet<ItemCat> ItemCats { get; set; }
    }
 protected override void OnModelCreating(DbModelBuilder mb)
        {
            mb.Configurations.Add(new ItemCatConfig());

            base.OnModelCreating(mb);
        }

but get:

System.NotSupportedException: The type 'ItemCat' cannot be mapped as defined because it maps inherited properties from types that use entity splitting or another form of inheritance. Either choose a different inheritance mapping strategy so as to not map inherited properties, or change all types in the hierarchy to map inherited properties and to not use splitting

Update: I also Read this

解决方案

Find the answer. just remove Map in ItemCatConfig Class.

 Map(m => { m.ToTable("ItemCats"); m.MapInheritedProperties(); });

In TPC abstract classes does not implement in db. ItemCat inherit from abstract classes and it doesn't need to Map configuration explicitly.

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