Fluent Api - Person and Creation

Question

I have a problem.I have two classes that I use in Entity Framework. First one is a person Class: With int id, string name and action creation(incl. Foreign Key). Second one is a action class. With id , time and a person(incl. Foreign Key). When I try to migrate this I get the an error that I should use the Fluent Api to create the relation between this. I searched a bit, but it seams to be a case that I couldn't find information about.

public class Person
{
    [Key]
    public int IdPerson { get; set; }

    public string Name{ get; set; }

    public int? CreationId { get; set; }
    [ForeignKey("CreationId")]
    public Action Creation{ get; set; }
}

public class Action
{
    [Key]
    public int IdAction { get; set; }

    [Required]
    [Column(TypeName = "DateTime2")]
    public DateTime Moment { get; set; }

    public int? PersonId { get; set; }
    [ForeignKey("PersonId")]
    public Person Person { get; set; }
}

The error message is in german:

Das Prinzipalende einer Zuordnung zwischen den Typen 'FunWeb.Models.Core.Person' und 'FunWeb.Models.Core.Aktion' konnte nicht ermittelt werden. Das Prinzipalende dieser Zuordnung muss mithilfe der Fluent-API für Beziehungen oder mithilfe von Datenanmerkungen explizit konfiguriert werden.

But it says that i need to configure the relation by my self.

Sorry for my english and thanks for your help

Edit: I tried:

modelBuilder.Entity<Person>().HasRequired(p => p.Creation).WithOptional(a => a.Person);

But i get the following error:

Das 'ForeignKeyAttribute' der Eigenschaft 'Person' für den Typ 'Models.Core.Action' ist ungültig. Der Fremdschlüsselname 'PersonId' wurde im abhängigen Typ 'Models.Core.Person' nicht gefunden. Der Name-Wert muss eine durch Trennzeichen getrennte Liste mit Namen von Fremdschlüsseleigenschaften sein.

I try to translate: ForeignKeyAttribute of the propaty Person for the type Action is in valid. The ForeignKey 'PersonId' could not by found in "Models.Core.Person". The name value needs to be a seperated list of names for ForeignKeyAttributes.

Sorry missed the preview button and hit sumit. I have updated it now. — user3460436, Oct 05 '15 at 08:12
Could you also add relevant code and full error message text? See [asking help](http://stackoverflow.com/help/how-to-ask) for further guidelines. — Alexander Obersht, Oct 05 '15 at 08:15

score 0 · Answer 1 · answered Oct 05 '15 at 08:47

Your problem is that ForeignKey attribute is responsible for One-To-Many relations. But it seems that you want to have one-to-one relatioins. To setup one-to-one you should use fluent api. It will be something like:

modelBuilder.Entity<Person>().HasRequired(p=>p.Creation).WithOptional(a=>a.Person)

Fluent Api - Person and Creation

1 Answers1