實體框架和模型與一個類別的字段

Question

我有「用戶」和「出價」模型。

Andcourse「Users」和「Bids」表在DateBase中。 （"Bid" columns in postgres table）

我可以映射一個「用戶」字段是這樣的：

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

，但不知道如何映射具有不同名稱的三大「用戶」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; } 

我該怎麼辦？

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

我懷疑你必須告訴Entity Framework了3個屬性應作爲數據庫中的外鍵。

由於它們具有非常規名稱（EF不會將它們自動識別爲外鍵），因此可以通過設置ForeignKey屬性來幫助理解它們，並指定它們是哪些導航屬性作爲外鍵值。

[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; }