首先使用代码在Entity Framework中进行问题建模关系
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我试图首先在Entity Framework中学习代码，但在建模关系时遇到了麻烦。这是一个基本的HR数据库，因此有两个实体，雇员和部门。
员工属于部门，部门有团队管理员和经理，两者实际上都是员工。我尝试使用以下方法对此进行建模：
EMPLOYEE
public int? DepartmentID { get; set; }
public virtual Department Department { get; set; }
Context:
modelBuilder.Entity<Employee>().HasOptional(x => x.Department);
DEPARTMENT
public class Department
{
[Required]
public int DepartmentID { get; set; }
[Required(ErrorMessage = \"The description is required.\")]
public string Description { get; set; }
public int? ManagerID { get; set; }
public virtual Employee Manager { get; set; }
public int? TeamAdministratorID { get; set; }
public virtual Employee TeamAdministrator { get; set; }
}
Context:
modelBuilder.Entity<Department>().HasOptional(x => x.Manager);
modelBuilder.Entity<Department>().HasOptional(x => x.TeamAdministrator);
没有找到相关结果
已邀请:
2 个回复
砷竣阿
modelBuilder.Entity<Employee>() .HasOptional(x => x.Department) .WithMany() .HasForeignKey(x => x.DepartmentID);modelBuilder.Entity<Department>() .HasOptional(x => x.Manager) .WithMany() .HasForeignKey(x => x.ManagerID); modelBuilder.Entity<Department>() .HasOptional(x => x.TeamAdministrator); .WithMany() .HasForeignKey(x => x.TeamAdministratorID);均为空）。至少应该具有：public virtual ICollection<Employee> Employees { get; set;}modelBuilder.Entity<Employee>() .HasOptional(x => x.Department) .WithMany(y => y.Employees) .HasForeignKey(x => x.DepartmentID);揽芳僵迷仇
EMPLOYEE public int? DepartmentID { get; set; } public virtual Department Department { get; set; }。默认情况下，EF搜索ID属性并为您链接两个类。因此，您的类应仅包含一个ID-类本身的ID。尝试删除其他类的ID。