实体框架代码优先和无效的对象名称错误

Question

我有一个名为 ImporterState 的复合表，它与名为 Importer 和 State 的表相关联。错误发生在这里context.Importers.Include(q => q.States)。为什么会这样？

{"无效的对象名称'ImporterStates'。"}

    [Table("HeadlineWebsiteImport", Schema = "GrassrootsHoops")]
        public class Importer
        {
            public int Id { get; set; }
            public string Name { get; set; }
            public string RssUrl { get; set; }
            public string Type { get; set; }
            public string Keywords { get; set; }
            public bool Active { get; set; }
            public DateTime DateModified { get; set; }
            public DateTime DateCreated { get; set; }

            public int WebsiteId { get; set; }

            public HeadlineWebsite Website { get; set; }

            [InverseProperty("Importers")]
            public ICollection<State> States { get; set; }
        }

[Table("State", Schema = "GrassrootsHoops")]
    public class State
    {
        [Key]
        public int Id { get; set; }
        public string Name { get; set; }
        public string Abbr { get; set; }

        [InverseProperty("States")]
        public ICollection<Headline> Headlines { get; set; }

        [InverseProperty("States")]
        public ICollection<Importer> Importers { get; set; }
    }

Answer 1

仅使用属性是不可能实现多对多的。

尝试使用类似的东西：

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

        modelBuilder.Entity<Importer>()
            .HasMany(i => i.States)
            .WithMany(s => s.Importers)
            .Map(m =>
                {
                    m.MapLeftKey("ImporterId");
                    m.MapRightKey("StateId");
                    m.ToTable("ImporterState");
                });
    }