Can I avoid the foreign key properties in my entity? - entity-framework

Question

I have the following classes:
public class Bicycle
{
public int BicycleId { get; set; }
public DateTime YearOfManufacture { get; set; }
public int BicycleManufactuerId { get; set; }
public BicycleManufacturer BicycleManufacturer { get; set; }
}
public class BicycleManufacturer
{
public int BicycleManufacturerId { get; set; }
public string Description { get; set; }
}
Each Bicycle must have a BicycleManufacturer (1:1). There could be some BicycleManufacturer that isn't associate with any Bicycle. Most will be associated with multiple Bicycle entities.
I have the following fluent API code to set up the FK relationship:
modelBuilder.Entity<Bicycle>()
.HasRequired(a => a.BicycleManufacturer)
.WithMany()
.HasForeignKey(u => u.BicycleManufactuerId);
This all seems to work fine. However, I would really like to remove the BicycleManufacturerId property from the Bicycle entity. It's only there to establish the FK relationship. Is there a way I can create the proper FK relationship if I remove this property?

Answer 1

You can remove the property and use the mapping:
modelBuilder.Entity<Bicycle>()
.HasRequired(a => a.BicycleManufacturer)
.WithMany()
.Map(m => m.MapKey("BicycleManufactuerId"));

Answer 2

You can also do it by convention by adding the relationship on the other side as a collection.
public class Bicycle
{
public int BicycleId { get; set; }
public DateTime YearOfManufacture { get; set; }
public int BicycleManufactuerId { get; set; }
public BicycleManufacturer BicycleManufacturer { get; set; }
}
public class BicycleManufacturer
{
public int BicycleManufacturerId { get; set; }
public ICollection<Bicycle> Bicycles { get; set; }
public string Description { get; set; }
}