如何在不同的表中映射兩個具有相同主鍵的不同外鍵？

Question

我有一個名為EnrollTrainee的表。 我的EnrollTrainee模型類中有以下列：

[Key]
public int id { get; set; }

public int TraineeID { get; set; }      

public int TrainerID { ![enter image description here][1]get; set; }

public virtual CreateUsers user_userid { get; set; }

public virtual CreateUsers user_id { get; set; }

public DateTime dt { get; set; }

這兩個列TraineeID和TrainerID將與表CreateUser中的 User_id列進行映射。

這是CreateUser模型類

    public class CreateUsers
    {
    [Key]
      public int User_Userid { get; set; }

    [Required]
    [Display(Name="Enter User Name")]
    public string User_name { get; set; }

    [Required]
    [Remote("IsDomainIDExist", "Account", ErrorMessage = "Domain ID Already Exist")]
    [Display(Name = "Enter Domain ID")]
    public string User_username { get; set; }

    [Required]
    [DataType(DataType.Password)]
    [Display(Name = "Enter Password")]
    public string User_password { get; set; }

    [Required]
    [Display(Name = "Enter Department")]
    public string User_department { get; set; }

    [Required]
    [Remote("IsEmployeeIDExist", "Account", ErrorMessage = "Domain ID Already Exist")]
    [Display(Name = "Enter Employee ID")]
    public string User_employeeid { get; set; }

    [Required]
    [Display(Name="Select Role Type")]
    public int RoleID { get; set; }

    [Display(Name="Enable?")]
    public bool User_Enable { get; set; }

    [DataType(DataType.DateTime)]
    [Display(Name = "Date Time")]
    public DateTime dt { get; set; }

    public virtual RoleModel Role { get; set; }

 }

如何在EF CF中映射兩個具有相同主鍵的外鍵？

Answer 1

像這樣：

public class EnrollTrainee
{
    [Key]
    public int id { get; set; }

    public int TraineeID { get; set; }

    public virtual CreateUser Trainee { get; set; }

    public int TrainerID { get; set; }

    public virtual CreateUser Trainer { get; set; }

    public DateTime dt { get; set; }
}

internal class EnrollTraineeConfiguration:EntityTypeConfiguration<EnrollTrainee>
{
    public EnrollTraineeConfiguration()
    {
        ToTable("EnrollTrainee");
        Property(c => c.dt).HasColumnName("dt");
        Property(c => c.TraineeID).HasColumnName("TraineeID");
        Property(c => c.TrainerID).HasColumnName("TrainerID");
        HasKey(c => c.id);
        HasRequired(c => c.Trainee).WithMany().HasForeignKey(c=>c.TraineeId);
        HasRequired(c => c.Trainer).WithMany().HasForeignKey(c => c.TrainerId);
    }
}
public class Context: DbContext
{
     protected override void OnModelCreating(DbModelBuilder modelBuilder)
     {
          modelBuilder.Configurations.Add(new EnrollTraineeConfiguration());
          ......
     }
     ....
}

Answer 2

如果您使用的是MVC3或4，則可以使用Entity Framework映射執行相同的操作，這將生成所需的類。 您可以使用模型瀏覽器執行相同的操作。

您要做的是：

創建表在表中創建PK和FK約束右鍵單擊項目中解決方案資源管理器中的“模型”文件夾，選擇“添加新項”，從“數據”類別中選擇ADO.Net EF 4.x / 5.x，單擊“確定”將打開一個向導，提供所需的參數，在選擇要查詢的表的方式上。 完成后，它將僅在.Edmx的上下文文件中創建一個.Edmx文件，