EF7多对多

Question

楷模:

public partial class Film
{
    public int FilmID { get; set; }
    public virtual ICollection<Genre> Genres { get; set; }
}

public class Genre
{
    public int GenreID { get; set; }

    public virtual ICollection<Film> Films { get; set; }
}

OnModel使用EF6创建

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<Film>()
                    .HasMany(e => e.Genres)
                    .WithMany(e => e.Films)
                    .Map(m => m.ToTable("Genre_Film").MapLeftKey("Films_IdFilm").MapRightKey("Genres_IdGenre"));
}

我使用SQLite.我如何使用EF7做同样的事情？

Answer 1

EF7的文档说明了如何实现这一目标:http://docs.efproject.net/en/latest/modeling/relationships.html#many-to-many

        modelBuilder.Entity<PostTag>()
            .HasOne(pt => pt.Post)
            .WithMany(p => p.PostTags)
            .HasForeignKey(pt => pt.PostId);

        modelBuilder.Entity<PostTag>()
            .HasOne(pt => pt.Tag)
            .WithMany(t => t.PostTags)
            .HasForeignKey(pt => pt.TagId);

        public class PostTag
        {
          public int PostId { get; set; }
          public Post Post { get; set; }
          public int TagId { get; set; }
          public Tag Tag { get; set; }
        }

Answer 2

映射API将在EF 7中更改.已经提出了一种更直观的一对多API.在那里有许多短语:

我们希望多对多API与一对多和一对一API非常相似.

但它尚未在当前来源中实施.在为测试创建的上下文中,它说:

// TODO: Many-to-many
//modelBuilder.Entity<TSupplier>().ForeignKeys(fk => fk.ForeignKey<TProduct>(e => e.SupplierId));

这就是我能找到的所有相关信息.

我当然希望EF7在这方面能够向后兼容.