实体配置:如何正确配置类和实体配置

Question

我的问题是，我是否在类和实体配置中做了正确的关系

我应该在哪里做1: n的关系？在船班还是InfoAppointment班？

我是在InfoAppointment做的，但我很怀疑。

InfoWeather，它将始终与InfoAppointment一起注册。InfoWeather不在其他地方注册，因此对于每个InfoAppointment条目记录，我可以拥有一个infoWeather，而且infoWeather也可以是可选的。

我也对0或1的配置有疑问，对吗？

我的类InfoAppointment只能有一个Boat

我的Boat类可以在多个InfoAppointment中。

我的类InfoAppointment可以有零个或一个InfoWeather

我的类InfoWeather可以有一个或零个InfoAppointment

public  class InfoAppointment : Entity
{
  public Guid Boat_Id { get; set; }
  public virtual Boat Boat { get; set; }
  public virtual InfoWeather infoWeather { get; set; }
}

public  class InfoWeather : Entity
{
  public virtual InfoAppointment InfoAppointment { get; set; }
}

public  class Boat : Entity
{
 public virtual ICollection<InfoAppointment> InfoAppointment { get; set; }
}



public class InfoAppointmentConfig : EntityTypeConfiguration<InfoAppointment>
{
  HasRequired(c => c.Boat)
              .WithMany(c => c.InfoAppointment )
              .HasForeignKey(c => c.Boat_Id);

   HasOptional(c => c.InfoWeather )
            .WithOptionalDependent(c => c.InfoAppointment );
}

public class BoatConfig : EntityTypeConfiguration<Boat>
{
}

public class InfoWeatherConfig : EntityTypeConfiguration<InfoWeather >
{
}

Answer 1

您的要求如下：

1. 我的类InfoAppointment只能有一个Boat
2. 我的类Boat可以在多个InfoAppointment中。
3. 我的类InfoAppointment可以有零个或一个InfoWeather
4. 我的类InfoWeather可以有一个或零个InfoAppointment

然后将InfoAppointment、Boat和InfoWeather之间的关系写成如下：

public  class InfoAppointment : Entity
{
  [Key]
  public Guid InfoAppointmentId { get; set; }

  [ForeignKey("Boat")]
  public Guid BoatId {get; set;}

  // other properties

  public virtual Boat Boat { get; set; }

  public virtual InfoWeather infoWeather { get; set; }
}

public  class Boat : Entity
{
   public Guid BoatId {get; set;}

   // other properties

   public virtual List<InfoAppointment> InfoAppointments { get; set; }
}

public  class InfoWeather : Entity
{
  [Key,ForeignKey("InfoAppointment")]
  public Guid InfoAppointmentId { get; set; }

  // other properties

  public virtual InfoAppointment InfoAppointment { get; set; }
}

直到第三项要求，一切都好。你的第四个要求

1. 我的类InfoWeather可以有一个或零个InfoAppointment

一定要确保你真的想要这个。然后，您必须按以下方式更新InfoAppointment和InfoWeather实体：

public  class InfoAppointment : Entity
{
  public Guid InfoAppointmentId { get; set; }

  [ForeignKey("Boat")]
  public Guid BoatId {get; set;}

  [ForeignKey("InfoWeather")]
  public Guid InfoWeatherId {get; set;}


  // other properties

  public virtual Boat Boat { get; set; }

  public virtual InfoWeather InfoWeather { get; set; }
}


public  class InfoWeather : Entity
{
  [Key]
  public Guid InfoWeatherId { get; set; }

  [ForeignKey("InfoAppointment")]
  public Guid InfoAppointmentId { get; set; }

  // other properties

  public virtual InfoAppointment InfoAppointment { get; set; }
}

现在必须使用FluentAPI指定主体实体如下：

modelBuilder.Entity<InfoAppointment>()
   .HasOptional(x => x.InfoWeather)
   .WithOptionalPrincipal(x => x.InfoAppointment)
   .Map(a => a.MapKey("InfoWeatherId"));

希望这对你有用！