类型中的属性名称必须是唯一的 [英] Property name in a type must be unique

问题描述

我正在使用Entity Framework 5，我有以下实体：

  public class User {
 public Int32 Id {get;组; } 
 public String Username {get;组; } 
 public virtual ICollection< CLaim> CLaims {get;组; } 
} 
 
 public class Claim {
 public Int32 Id {get;组; } 
 public String Type {get;组; } 
 public String Value {get;组; } 
 public virtual User User {get;组; 
} 
  

有关这些实体的几个注释：

1. 在用户实体中，Id是PK;


2. 在Claim实体中，Id是FK，等于User.Id;


3. 在索赔实体中，PK是从（Id，Type，Value）复合到$ /
   
   

   我有这些实体的以下SQL：

    创建表dbo.Users 
   （
    Id int identity不为空
   约束PK_Users_Id主键集群（Id），
   用户名nvarchar（120）not null 
   约束UQ_Users_Username unique（Username）
   ）; 
    
   创建表dbo.Claims 
   （
    Id int not null，
    [Type] nvarchar（200）not null，
   值nvarchar（200）不为空，
   约束PK_Claims_Id_Type_Value主键（Id，[Type]，Value），
   ）; 
    
    alter table dbo.Claims 
   添加约束FK_CLaims_Id外键（Id）
   引用删除级联上的dbo.Users（Id）更新级联; 
     

   最后，实体的配置如下：

    内部类UserConfiguration：EntityTypeConfiguration< User> {
   内部UserConfiguration（）：base（）{
    ToTable（Users）; 
    HasKey（x => x.Id）; 
   属性（x => x.Id）.IsRequired（）。HasDatabaseGeneratedOption（DatabaseGeneratedOption.Identity）; 
   属性（x => x.Username）.IsRequired（）。HasMaxLength（120）; 
   } 
   } 
    
   内部类ClaimConfiguration：EntityTypeConfiguration< Claim> {
    internal ClaimMapper（）：base（）{
    ToTable（Claims）; 
    HasKey（x => new {x.Id，x.Type，x.Value}）; 
   属性（x => x.Id）.IsRequired（）。HasDatabaseGeneratedOption（DatabaseGeneratedOption.None）; 
   属性（x => x.Type）.IsRequired（）。HasMaxLength（200）; 
   属性（x => x.Value）.IsRequired（）。HasMaxLength（200）; 
    
    HasRequired< User>（x => x.User）.WithMany（y => y.Claims）.Map（z => {z.MapKey（Id）;} ）; 
   } 
   } 
     

   问题： / p>
   
   

   当我尝试创建一个用户时，我收到以下错误：

   
   

   每个类型中的属性名称必须是唯一的。属性名称'Id'已被定义。

   
   

   有谁知道我可能做错了什么？

   
   只有当您的外键列未作为模型中的属性公开时，才会使用MapKey

   解决方案

   但在你的情况下，它是 - 作为属性 Claim.Id 。在这种情况下，您必须使用 HasForeignKey 而不是 MapKey ：

     HasRequired< User>（x => x.User）
    .WithMany（y => y.Claims）
    .HasForeignKey（x => x.Id）; 
     

   


   I am using Entity Framework 5 and I have the following entities:

   public class User {
     public Int32 Id { get; set; }
     public String Username { get; set; }    
     public virtual ICollection<CLaim> CLaims { get; set; }
   }
   
   public class Claim {
     public Int32 Id { get; set; }
     public String Type { get; set; }
     public String Value { get; set; }
     public virtual User User { get; set; }
   }
   

   A few notes about these entities:

   1. In User entity the Id is the PK;
   2. In Claim entity the Id is a FK and is equal to User.Id;
   3. In Claim entity the PK is composite from (Id, Type, Value)

   So I have the following SQL for these entities:

   create table dbo.Users
   (
     Id int identity not null 
       constraint PK_Users_Id primary key clustered (Id),  
     Username nvarchar (120) not null
       constraint UQ_Users_Username unique (Username)
   );
   
   create table dbo.Claims
   (
     Id int not null,
     [Type] nvarchar (200) not null,
     Value nvarchar (200) not null,
       constraint PK_Claims_Id_Type_Value primary key (Id, [Type], Value),
   );
   
   alter table dbo.Claims
   add constraint FK_CLaims_Id foreign key (Id) 
       references dbo.Users(Id) on delete cascade on update cascade;
   

   Finally, the configuration of the entities are as follows:

   internal class UserConfiguration : EntityTypeConfiguration<User> {
     internal UserConfiguration() : base() {
       ToTable("Users");
       HasKey(x => x.Id);
       Property(x => x.Id).IsRequired().HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
       Property(x => x.Username).IsRequired().HasMaxLength(120);
     }
   }
   
   internal class ClaimConfiguration : EntityTypeConfiguration<Claim> {
     internal ClaimMapper() : base() {
       ToTable("Claims");
       HasKey(x => new { x.Id, x.Type, x.Value });
       Property(x => x.Id).IsRequired().HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);
       Property(x => x.Type).IsRequired().HasMaxLength(200);
       Property(x => x.Value).IsRequired().HasMaxLength(200);
   
       HasRequired<User>(x => x.User).WithMany(y => y.Claims).Map(z => { z.MapKey("Id"); });
     }
   }
   

   THE PROBLEM:

   When I try to create a user I get the following error:

   Each property name in a type must be unique. Property name 'Id' was already defined.

   Does anyone knows what I might be doing wrong?

   解决方案

   MapKey is only used if your foreign key column is not exposed as a property in your model. But in your case it is - as property Claim.Id. In that case you must use HasForeignKey instead of MapKey:

   HasRequired<User>(x => x.User)
       .WithMany(y => y.Claims)
       .HasForeignKey(x => x.Id);
   

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