我基本上有一个新的MVC5 / EF6（个人用户身份验证）项目，我正在尝试稍微修改Identity Users表，以包含国家，州和城市的ID。我能够通过EF Migrations成功创建新列，但在尝试添加FK约束时，我遇到了障碍。我将CountryId，StateId和CityId添加到默认的Identity Users SQL表中，所有这些都设置为可以为空的Int值。
所以，我有三个类似的国家，州，市（显示State.cs）类：
public class State
{
[Key]
public int StateId { get; set; }
public string StateName { get; set; }
[ForeignKey("Country")]
public int CountryId { get; set; }
public virtual Country Country { get; set; }
public virtual ICollection<City> Cities { get; set; }
public virtual ApplicationUser ApplicationUser { get; set; }
}
然后我在IdentityModels.cs ApplicationUser类中有了这个额外的代码块：
public class ApplicationUser : IdentityUser
{
[ForeignKey("Country")]
public int CountryId { get; set; }
[ForeignKey("State")]
public int StateId { get; set; }
[ForeignKey("City")]
public int CityId { get; set; }
public virtual Country Country { get; set; }
public virtual State State { get; set; }
public virtual City City { get; set; }
// the rest is default....
}
看起来很简单。但是，它在尝试添加迁移时不喜欢我：
PM> Add-Migration AddLocaleForeignKeys
System.Data.Entity.ModelConfiguration.ModelValidationException: One or more validation errors were detected during model generation:
ApplicationUser_City_Source: : Multiplicity is not valid in Role 'ApplicationUser_City_Source' in relationship 'ApplicationUser_City'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be '*'.
ApplicationUser_Country_Source: : Multiplicity is not valid in Role 'ApplicationUser_Country_Source' in relationship 'ApplicationUser_Country'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be '*'.
ApplicationUser_State_Source: : Multiplicity is not valid in Role 'ApplicationUser_State_Source' in relationship 'ApplicationUser_State'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be '*'.
at System.Data.Entity.Core.Metadata.Edm.EdmModel.Validate()
at System.Data.Entity.DbModelBuilder.Build(DbProviderManifest providerManifest, DbProviderInfo providerInfo)
at System.Data.Entity.DbModelBuilder.Build(DbConnection providerConnection)
at System.Data.Entity.Internal.LazyInternalContext.CreateModel(LazyInternalContext internalContext)
at System.Data.Entity.Internal.RetryLazy`2.GetValue(TInput input)
at System.Data.Entity.Internal.LazyInternalContext.InitializeContext()
at System.Data.Entity.Internal.LazyInternalContext.get_ModelBeingInitialized()
at System.Data.Entity.Infrastructure.EdmxWriter.WriteEdmx(DbContext context, XmlWriter writer)
at System.Data.Entity.Utilities.DbContextExtensions.<>c__DisplayClass1.<GetModel>b__0(XmlWriter w)
at System.Data.Entity.Utilities.DbContextExtensions.GetModel(Action`1 writeXml)
at System.Data.Entity.Utilities.DbContextExtensions.GetModel(DbContext context)
at System.Data.Entity.Migrations.DbMigrator..ctor(DbMigrationsConfiguration configuration, DbContext usersContext, DatabaseExistenceState existenceState, Boolean calledByCreateDatabase)
at System.Data.Entity.Migrations.DbMigrator..ctor(DbMigrationsConfiguration configuration)
at System.Data.Entity.Migrations.Design.MigrationScaffolder..ctor(DbMigrationsConfiguration migrationsConfiguration)
at System.Data.Entity.Migrations.Design.ToolingFacade.ScaffoldRunner.Run()
at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate)
at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate)
at System.Data.Entity.Migrations.Design.ToolingFacade.Run(BaseRunner runner)
at System.Data.Entity.Migrations.Design.ToolingFacade.Scaffold(String migrationName, String language, String rootNamespace, Boolean ignoreChanges)
at System.Data.Entity.Migrations.AddMigrationCommand.Execute(String name, Boolean force, Boolean ignoreChanges)
at System.Data.Entity.Migrations.AddMigrationCommand.<>c__DisplayClass2.<.ctor>b__0()
at System.Data.Entity.Migrations.MigrationsDomainCommand.Execute(Action command)
One or more validation errors were detected during model generation:
ApplicationUser_City_Source: : Multiplicity is not valid in Role 'ApplicationUser_City_Source' in relationship 'ApplicationUser_City'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be '*'.
ApplicationUser_Country_Source: : Multiplicity is not valid in Role 'ApplicationUser_Country_Source' in relationship 'ApplicationUser_Country'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be '*'.
ApplicationUser_State_Source: : Multiplicity is not valid in Role 'ApplicationUser_State_Source' in relationship 'ApplicationUser_State'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be '*'.
我已经阅读了其他一些类似的问题，我希望有人可以在我的代码中向我展示（在精神上受到挑战的条款）我做错了什么，因为我没有从术语中得到它立场（或查看他们的代码）。从基本上解剖了这个链接HERE
，我得到了关于做FK的想法我也愿意采取其他方式，因为我正在考虑使用所有这些信息做一个UserSettings表，然后用UserId或类似的东西做一个FK约束。但是，这种方式对我来说似乎是一个额外的不必要的表格。
我很感激帮助。
答案 0 :(得分：0)
问题是你正在创建三个一对一的关系，在这种关系中，EF期望两个相关的表共享相同的主键值（一个表的主键也是PK和外键）其他），但我认为这不是你的情况，因为同一个State可能在几个ApplicationUsers中，所以，你需要配置一对多的关系。
public class State
{
[Key]
public int StateId { get; set; }
public virtual ICollection<ApplicationUser> ApplicationUsers { get; set; }
}
public class ApplicationUser : IdentityUser
{
//...
[ForeignKey("State")]
public int StateId { get; set; }
public virtual State State { get; set; }
}
对Country和City实体执行相同操作。
答案 1 :(得分：0)
对于我上面的问题，接受的答案在技术上是正确的。但是，我找到了另一个我正在寻找的答案（上面也提到过），这也巩固了我不赌博的原因。
在我的最后一段中，我注意到我愿意采用其他方式...以下msdn博客也描述了我所指的内容（具有由单个FK链接的单独用户设置表）：
我意识到我可以这样做，但现在我正在寻找一个无错模型等等（感谢octavioccl），尝试从头开始生成代码肯定会让我的大脑爆炸。我现在纯粹是从仅示例模式中学习。无论如何，希望这个答案可以帮助其他人节省时间并克服这些学习障碍。
现在，我将不得不看看我是否可以融化我的大脑试图撤消所有EF迁移的东西并回到我开始的地方。也许我会重新开始......再次......