多于一个的导航，同一个实体 [英] more than one navigation to the same entity

问题描述

我有2实体时，有2导航之间的连接问题

I have a problem with connection between 2 entities when there is 2 navigations.

是具体的，我有以下类：

to be specific, I have the following classes:

public class TableA
{
    public TableA()
    {
        ListBs = new List<TableB>();
    }

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

    public TableB MainB { get; set; }

    public virtual ICollection<TableB> ListBs { get; set; }
}

public class TableB
{
    [Key]
    public int Id { get; set; }

    public virtual TableA refA { get; set; }

    [Required]
    public string Text { get; set; }

}

这个特殊类的场景反映了以下几点：
表A具有表b的对象的列表
和还具有1个主表b对象（即课程列表中的太）。
也是一个表B对象不能actualy有表A

The scenario of this particular classes reflects the following: TableA has a list of TableB objects and also has 1 main TableB object(that is of course in the list too). Also a TableB object may not actualy have a reference to TableA

取作品的引用。
，但是当我尝试插入新项目出现以下异常：

the fetching works. but when I try to insert new items I get the following exception:

无法确定相关的操作有效的排序。依赖可能存在由于外键约束，模型要求，或存储生成的值。

Unable to determine a valid ordering for dependent operations. Dependencies may exist due to foreign key constraints, model requirements, or store-generated values.

任何想法，我有什么错？

Any idea where I got anything wrong?

推荐答案

使用此代码：

public class TableA
{
    public TableA()
    {
        ListBs = new List<TableB>();
    }

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

    public int TableB_Id { get; set; }

    [InverseProperty("TableA_Mains")]
    [ForeignKey("TableB_Id")]
    public TableB MainB { get; set; }

    [InverseProperty("refA")]
    public virtual ICollection<TableB> ListBs { get; set; }
}

public class TableB
{
    [Key]
    public int Id { get; set; }

    public int TableA_Id { get; set; }

    [Foreignkey("TableA_Id")]
    [InverseProperty("ListBs")]
    public virtual TableA refA { get; set; }

    [Required]
    public string Text { get; set; }


    [InverseProperty("MainB")]
    public virtual ICollection<TableA> TableA_Mains { get; set; }

}

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