网络上常常看到有ef 1对1 1对多等关系的描述，按照我的理解，其根本就是为了呈现出一个视图，我最近设计了一个ef关系，请大家看一看。
需求描述
在gps车辆信息管理中，有个开户需求，其根本就是三种关系的对应，车辆信息，sim卡信息，以及终端信息，这三个实体是一一对应的，一旦开户，就需要三种信息。
先设计三种关系实体
/// <summary>
/// 实体模型抽象类
/// </summary>
public abstract class DbSetBase : IDbSetBase
{
/// <summary>
/// 构造函数
/// </summary>
public DbSetBase()
{
Id = Guid.NewGuid();
CreatedDate = DateTime.Now;
Deleted = false;
}
/// <summary>
/// 唯一Id
/// </summary>
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public Guid Id { get; set; }
/// <summary>
/// 创建时间
/// </summary>
public DateTime CreatedDate { get; set; }
/// <summary>
/// 更新时间
/// </summary>
public DateTime? UpdatedDate { get; set; }
/// <summary>
/// 是否删除
/// </summary>
public bool Deleted { get; set; }
/// <summary>
/// 备注
/// </summary>
public string Remark { get; set; }
}
/// <summary>
/// 车辆数据
/// </summary>
[Table("S_VehicleInfo")]
public class VehicleInfo : DbSetBase
{
/// <summary>
/// 车牌号
/// </summary>
public string VehicleNo { get; set; }
/// <summary>
/// 车牌颜色
/// </summary>
public VehicleColor Color { get; set; }
/// <summary>
/// 企业信息
/// </summary>
public Guid EnterpriseId { get; set; }
/// <summary>
/// 企业信息
/// </summary>
[ForeignKey("EnterpriseId")]
public virtual Enterprise Enterprise { get; set; }
/// <summary>
/// 使用状态
/// </summary>
public UsingType UsingType { get; set; }
/// <summary>
/// 开户信息
/// </summary>
public virtual OpenAccount Account { get; set; }
/// <summary>
/// 所属车队
/// </summary>
public Guid? CompanyId { get; set; }
/// <summary>
/// 所属车队
/// </summary>
[ForeignKey("CompanyId")]
public virtual Company Company { get; set; }
}
/// <summary>
/// 终端信息
/// </summary>
[Table("S_TerminalInfo")]
public class TerminalInfo : DbSetBase
{
/// <summary>
/// 终端Id
/// </summary>
public string TerminalNo { get; set; }
/// <summary>
/// 终端类型
/// </summary>
public string TerminalType { get; set; }
/// <summary>
/// 使用状态
/// </summary>
public UsingType UsingType { get; set; }
/// <summary>
/// 开户信息
/// </summary>
public virtual OpenAccount Account { get; set; }
}
/// <summary>
/// Sim信息
/// </summary>
[Table("S_SimInfo")]
public class SimInfo : DbSetBase
{
/// <summary>
/// 手机号
/// </summary>
public string PhoneNo { get; set; }
/// <summary>
/// Sim卡号
/// </summary>
public string SimNo { get; set; }
/// <summary>
/// 使用状态
/// </summary>
public UsingType UsingType { get; set; }
/// <summary>
/// 开户信息
/// </summary>
public virtual OpenAccount Account { get; set; }
}
/// <summary>
/// 开户信息
/// </summary>
[Table("OpenAccount")]
public class OpenAccount : DbSetBase
{
/// <summary>
/// 终端信息
/// </summary>
public virtual TerminalInfo Terminal { get; set; }
/// <summary>
/// 车辆信息
/// </summary>
public virtual VehicleInfo Vehicle { get; set; }
/// <summary>
/// Sim信息
/// </summary>
public virtual SimInfo Sim { get; set; }
/// <summary>
/// 注册时间
/// </summary>
public DateTime? RegisterTime { get; set; }
/// <summary>
/// 是否注册
/// </summary>
public bool? IsRegister { get; set; }
}
}
，在通过 Fluent Api设计其对应关系：
modelBuilder.Entity<OpenAccount>().HasRequired(a => a.Vehicle).WithOptional(b => b.Account).Map(m => m.MapKey("VehicleId"));
modelBuilder.Entity<OpenAccount>().HasRequired(a => a.Sim).WithOptional(b => b.Account).Map(m => m.MapKey("SimId"));
modelBuilder.Entity<OpenAccount>().HasRequired(a => a.Terminal).WithOptional(b => b.Account).Map(m => m.MapKey("TerminalId"));
这样三种对象的对应关系就完成了，开户信息表就是作为一种视图来呈现三种对象的对应。