Mapping from many-to-many in database to one-to-many in domain

Question

I have a mapping challange in Entity Framework.

In the database I have a many-to-many relation between two tables with a intermediate table with the PK of the both as bellow:

I need to map this relation to a one-to-many domain entities relation as bellow:

How can I map this using Fluent API?

Answer 1

You can use a navigation property and set the Dependents table in the model:

public class Title
{
    public int Id { get; set; }

    public string Name { get; set; }

    public virtual ICollection<Person> Dependents { get; set; }
}

public class Person
{
    public int Id { get; set; }

    public string Name { get; set; }
}

public class MyContext : DbContext
{
    public DbSet<Title> Titles { get; set; }
    public DbSet<Person> People { get; set; }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        modelBuilder.Entity<Title>()
            .HasMany<Person>(t => t.Dependents)
            .WithMany()
            .Map(d =>
            {
                d.MapLeftKey("Title_Id");
                d.MapRightKey("Person_Id");
                d.ToTable("Dependents");
            });
    }
}