如何在EF6中对不同的实体使用同一张表

// 实体类
[Table("MyTable")]
public class EntityA
{
    [Column("Id")]
    public int Id { get; set; }

    [Column("Name")]
    public string Name { get; set; }
}

[Table("MyTable")]
public class EntityB : EntityA
{
    [Column("Value")]
    public int Value { get; set; }
}

// 上下文类
public class MyContext : DbContext
{
    public DbSet<EntityA> Entities { get; set; }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Entity<EntityA>()
            .HasKey(e => e.Id);

        modelBuilder.Entity<EntityB>()
            .Property(e => e.Value)
            .HasColumnName("Value");

        base.OnModelCreating(modelBuilder);
    }
}