C# 包括关联表中的数据

我想问一下如何在我的案例中包含数据。我已经创建了一个关联表，在其中定义

BusinessGlosItems

之间的关系。在下一步中，我创建了

BusinessGlosItems

的模型，并通过子关系和父关系包含了参考表

最后，我需要显示

BusinessGlosItems

及其所有相关数据的详细信息。听起来很容易，但我不知道如何解决这个问题。有人能帮忙吗

我的域类如下所示：

public class BusinessGlosItem
{
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int Id { get; set; }
    public string BGIName { get; set; }

    [InverseProperty("ChildBGItem")]
    public ICollection<Reference> ChildReferences { get; set; }
    [InverseProperty("ParentBGItem")]
    public ICollection<Reference> ParentReferences { get; set; }
}

public class Reference
{
    public int Id { get; set; }
    [ForeignKey("ChildBGItem")]
    public int? ChildGlosItemId { get; set; }
    [ForeignKey("ParentBGItem")]
    public int? ParentGlosItemId { get; set; }

    public int ReferenceTypeId { get; set; }

    public virtual ReferenceType ReferenceType { get; set; }

    public virtual BusinessGlosItem ChildBGItem { get; set; }

    public virtual BusinessGlosItem ParentBGItem { get; set; }
}

BusinessGlosItem = await _context.businessGlosItem                 
            .Include(x => x.BusinessArea)
            .Include(x => x.BusinessGlosItemStatus)
            .Include(x => x.ChildReferences)
                .ThenInclude(x=>x.ReferenceType)
            .Include(x => x.ChildReferences) // You missed this include
                .ThenInclude(x=>x.ChildBGItem)
            .Include(x => x.ChildReferences) // You missed this include
                .ThenInclude(x=>x.ParentBGItem)
            .Include(x => x.ParentReferences)
                .ThenInclude(x=>x.ReferenceType)
            .Include(x => x.ParentReferences) // You missed this include
                .ThenInclude(x=>x.ChildBGItem)
            .Include(x => x.ParentReferences) // You missed this include
                .ThenInclude(x=>x.ParentBGItem)
            .Include(x=>x.businessGlosItemComments)
            .SingleOrDefaultAsync(m => m.Id == id);

---

提前多谢

您忘了在

ChildReferences

和

ParentReferences

中同时提及

ChildBGItem

和

ParentReferences

的

。因此，您的查询应如下所示：

public class BusinessGlosItem
{
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int Id { get; set; }
    public string BGIName { get; set; }

    [InverseProperty("ChildBGItem")]
    public ICollection<Reference> ChildReferences { get; set; }
    [InverseProperty("ParentBGItem")]
    public ICollection<Reference> ParentReferences { get; set; }
}

public class Reference
{
    public int Id { get; set; }
    [ForeignKey("ChildBGItem")]
    public int? ChildGlosItemId { get; set; }
    [ForeignKey("ParentBGItem")]
    public int? ParentGlosItemId { get; set; }

    public int ReferenceTypeId { get; set; }

    public virtual ReferenceType ReferenceType { get; set; }

    public virtual BusinessGlosItem ChildBGItem { get; set; }

    public virtual BusinessGlosItem ParentBGItem { get; set; }
}

BusinessGlosItem = await _context.businessGlosItem                 
            .Include(x => x.BusinessArea)
            .Include(x => x.BusinessGlosItemStatus)
            .Include(x => x.ChildReferences)
                .ThenInclude(x=>x.ReferenceType)
            .Include(x => x.ChildReferences) // You missed this include
                .ThenInclude(x=>x.ChildBGItem)
            .Include(x => x.ChildReferences) // You missed this include
                .ThenInclude(x=>x.ParentBGItem)
            .Include(x => x.ParentReferences)
                .ThenInclude(x=>x.ReferenceType)
            .Include(x => x.ParentReferences) // You missed this include
                .ThenInclude(x=>x.ChildBGItem)
            .Include(x => x.ParentReferences) // You missed this include
                .ThenInclude(x=>x.ParentBGItem)
            .Include(x=>x.businessGlosItemComments)
            .SingleOrDefaultAsync(m => m.Id == id);

现在它应该可以工作了。
您正试图显示
BusinessGlosItem
及其
ChildReferences
和
ParentReferences
的详细信息，是吗？或者别的什么？是的，我需要知道孩子和父母的名字好的！现在告诉我您现有的代码有什么问题吗？当我执行此代码时：@foreach（Model.BusinessGlosItem.ParentReferences中的var项）{@item.ReferenceType.ReferenceTypeName@item.ParentBGItem.BGIName@item.ChildBGItem.BGIName//这里我想查看ChildItem名称}我收到此错误：NullReferenceException:对象引用未设置为对象的实例。在@item.ChildBGItem.BGIName行