在EF4 CTP4 Code First中包含附加列的连接表

Question

鉴于此sql架构:

create table [dbo].[Courses_Students] (
    [DummyColumn] [int] null,
    [CourseId] [int] not null,
    [StudentId] [int] not null,
    primary key ([CourseId], [StudentId])
);

如何定义复合主键和其他列EntityConfiguration？

Answer 1

你需要申报一个班级 Courses_Students

public class Courses_Students
{
    [Key]
    public int CourseId { get; set; }
    public int StudentId { get; set; }
    public int DummyColumn { get; set; }

    public virtual ICollection<Course> Courses { get; set; }
    public virtual ICollection<Student> Students { get; set; }
}

CourseId上的Key是为了防止编译错误,接下来你将覆盖它.

然后,在您的DbContext类中,您重写OnModelCreating,如下所示:

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<Courses_Students>()
        .HasKey(e => new { e.CourseId, e.StudentId })
        .MapSingleType()
        .ToTable("Courses_Students");
}