EF Core 3.0 1:0 与流利的关系

Question

EF Core 3.0...我找不到这个完全正常映射的精确答案。
Principal 到 Dependent，没有指向 Principal 的后向指针，1:0 关系，类型对象/查找 table 设置。问题是对象键名 "RunId" 不同于 EFCore 生成的键名 "ServiceRunId"

如何使用 Fluent API 替换 [ForeignKey("aServiceRun")] 注解？

这是我当前的 Fluent 设置，但我不知道将 ForeignKey 映射放在哪里。

aBuilder.Entity().HasKey(新字符串[] { "RunId "});

aBuilder.Entity<服务>().HasOne(s => s.aServiceRun);

Class Service {        
  public int ServiceId {get; set;}

  [ForeignKey("aServiceRun")]
  public int RunId { get; set; }

  public virtual ServiceRun aServiceRun { get; set; }
}

Class ServiceRun {
  public int RunId { get; set; }

  public string description {get ;set; }
}

表格：

Service {
  ServiceId int

  RunId int
}

SerivceRun {
  RunId int

  Description string
}

Answer 1

How can I use Fluent API to replace the [ForeignKey("aServiceRun")] annotation?

您正在寻找 HasForeignKey fluent API. But in order to get access to it (and other relationship configuration APIs), you need to define the relationship by using Has{One|Many} followed by With{One|Many}. For one-to-one 关系，您还需要向 HasForeignKey 提供通用类型参数：

When configuring the relationship with the Fluent API, you use the HasOne and WithOne methods.

When configuring the foreign key you need to specify the dependent entity type - notice the generic parameter provided to HasForeignKey in the listing below. In a one-to-many relationship it is clear that the entity with the reference navigation is the dependent and the one with the collection is the principal. But this is not so in a one-to-one relationship - hence the need to explicitly define it.

请注意，包含 FK 的实体始终是 dependent，因此对于您的模型，ServiceRun 是主体，Service 是从属，流畅的配置如下：

modelBuilder.Entity<Service>()
    .HasOne(s => s.aServiceRun) // navigation property
    .WithOne() // no navigation property
    .HasForeignKey<Service>(s => s.RunId); // foreign key

Answer 2

我找到了上述问题的答案 - 我的 ServiceRun 对象上有一个未配置或被忽略的反向列表。我决定把它留在这里作为另一个例子。也许它会为某人提供一些价值。

这是从服务到 ServiceRunType 的 1:0，其中 table 名称和 property/field 名称不完全匹配。

表格

ServiceRun { //Does not match object name
int Id, 
string Desc
}
Service {
int Id, 
int RunId //Does not match object
}

对象

Class ServiceRunType{  //Does not match table name
public int Id {get; set;} 
public String Desc {get; set;}
}
Class Service{
public int Id {get; set;} 
public int RunTypeId {get; set;} //Does not match table
public virtual ServiceRunType aServiceRunType { get; set; }
}

流畅代码

modelBuilder.Entity<ServiceRunType>()
.ToTable("ServiceRun", schema: "load")
.HasKey(new string[] { "Id" });
modelBuilder.Entity<Service>()
.ToTable("Service", schema: "load") //Had to specify schema
.HasKey(new string[] { "Id" });
modelBuilder.Entity<Service>()
.Property("RunTypeId")
.HasColumnName("RunId");
modelBuilder.Entity<Service>()
.HasOne(s => s.aServiceRunType)
.WithOne()
.HasForeignKey<Service>(s => s.RunTypeId);

EF Core 3.0 1:0 与流利的关系

EF Core 3.0 1:0 relationship with fluent

mapping

entity-framework

fluent

ef-core-3.1