Entity Framework - The foreign key component … is not a declared property on type

Question

I have the following Model

public class FilanthropyEvent :  EntityBase, IDeleteable {       public int Id { get; set; }     public string Name { get; set; }     public DateTime EventDate { get; set; }     public string Description { get; set; }     public decimal Target { get; set; }     public decimal EntryFee { get; set; }     public bool Deleted { get; set; }      public ICollection<EventAttendee> EventAttendees { get; set; } }  public class Attendee : EntityBase, IDeleteable {     public int Id { get; set; }     public string Email { get; set; }     public string FirstName { get; set; }     public string LastName { get; set; }     public bool MailingList { get; set; }     public bool Deleted { get; set; }      public ICollection<EventAttendee> EventAttendees { get; set; } } 

Events and Attendees is a many to many relationship but I needed another property on the association so I created an association entity

 public class EventAttendee : EntityBase  {     public int FilanthropyEventId { get; set; }     public int AttendeeId { get; set; }     public bool InActive { get; set; }      public virtual Attendee Attendee { get; set; }     public virtual FilanthropyEvent FilanthropyEvent { get; set; }  } 

These are the configurations for each FilanthropyEvent and Attendee

public class FilanthropyEventConfiguration : EntityTypeConfiguration<FilanthropyEvent> {        public FilanthropyEventConfiguration()        {            HasKey(x => x.Id);            Property(x => x.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);             HasMany(x => x.EventAttendees).WithRequired(x =>      x.FilanthropyEvent).HasForeignKey(x => x.FilanthropyEvent);        } }  public AttendeeConfiguration() {         HasKey(x => x.Id);         Property(x => x.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);          HasMany(x => x.EventAttendees).WithRequired(x => x.Attendee).HasForeignKey(x => x.AttendeeId); }  public class EventAttendeesConfiguration : EntityTypeConfiguration<EventAttendee> {     public EventAttendeesConfiguration()     {         HasKey(x => new {x.FilanthropyEventId, x.AttendeeId});     } } 

When I try and initialise the database via the update-database command in the package manager console I get the following error.

System.InvalidOperationException: The foreign key component 'FilanthropyEvent' is not a declared property on type 'EventAttendee'. Verify that it has not been explicitly excluded from the model and that it is a valid primitive property.

I realise I'm probably missing a mapping in the EventAttendeesConfiguration class but what would be the correct mapping to model this relationship?

Answer 1

This code

HasMany(x => x.EventAttendees) .WithRequired(x => x.FilanthropyEvent) .HasForeignKey(x => x.FilanthropyEvent); 

Should be

HasMany(x => x.EventAttendees) .WithRequired(x => x.FilanthropyEvent) .HasForeignKey(x => x.FilanthropyEventId);