具有一类字段的实体框架和模型[关闭]

Question

我有“用户”和“出价”模型。

当然还有 DateBase 中的“Users”和“Bids”表。 ("Bid" columns in postgres table)

我可以像这样映射一个“用户”字段：

    public int UserId { get; set; }
    public virtual User User { get; set; }

但不知道如何映射三个具有不同名称的“用户”字段。

    public int CreatorId { get; set; }//id of user in db table
    public int ManagerId { get; set; }//id of user in db table
    public int ExecutorId { get; set; }//id of user in db table
    public virtual User Creator { get; set; }
    public virtual User Manager { get; set; }
    public virtual User Executor { get; set; }

我该怎么办？

public class Bid
{
    public int BidId { get; set; }

    public string Title { get; set; }
    public string Text { get; set; }

    public DateTime DateOfCreating { get; set; }
    public DateTime DateOfProcessing { get; set; }
    public DateTime DateOfExecution { get; set; }

    //here is something incorrect
    public int CreatorId { get; set; }
    public int ManagerId { get; set; }
    public int ExecutorId { get; set; }
    public virtual User Creator { get; set; }
    public virtual User Manager { get; set; }
    public virtual User Executor { get; set; }

    public bool IsProcessed { get; set; }
    public bool IsExecuted { get; set; }
    public bool IsExecutionConfirmed { get; set; }
}

Answer 1

我怀疑你必须告诉Entity Framework 这三个属性应该用作数据库中的外键。

由于它们具有非常规名称（EF 不会自动将它们识别为外键），您可以通过在它们上设置 ForeignKey 属性并指定它们是外键值的导航属性来帮助它理解。

[ForeignKey("Creator")]
public int CreatorId { get; set; }

[ForeignKey("Manager")]
public int ManagerId { get; set; }

[ForeignKey("Executor")]
public int ExecutorId { get; set; }

public virtual User Creator { get; set; }
public virtual User Manager { get; set; }
public virtual User Executor { get; set; }