.net - モデルの関連データが読み込まれないのはなぜですか？

Question

私は最初にEF4コードで構築されたDBを持っています、ここに2つのモデルがあります：

Public Class HvacAudit
    Public Property HvacAuditID As Integer

    Public Overridable Property HvacAuditPictures As IEnumerable(Of HvacAuditPicture)

    ... other properties
 End Class

Public Class HvacAuditPicture
    Public Property HvacAuditPictureID As Integer

    Public Property HvacAuditID As Integer
    Public Overridable Property HvacAudit As HvacAudit

    ... other properties
End Class

データベースからHvacAuditレコードをプルすると、HvacAuditPicturesがありません。写真を直接引っ張ってもそこにあります。検討

context.HvacAudits.Where(Function(hva) hva.HvacAuditID = 1).HvacAuditPictures Is Nothing 'evaluates true

context.HvacAuditPictures.Where(Function(p) p.HvacAuditID = 1).Count() 'is currently 20

これが私のコンテキストクラスです：

Public Class EfContext
Inherits DbContext
Implements IDataSource

Public Property HvacAudits As IDbSet(Of HvacAudit) Implements IDataSource.HvacAudits
Public Property Vendors As IDbSet(Of Vendor) Implements IDataSource.Vendors
Public Property HvacAuditPictures As IDbSet(Of HvacAuditPicture) Implements IDataSource.HvacAuditPictures
Public Property Sites As IDbSet(Of Site)
Public Property Markets As IDbSet(Of Market)

Public Sub SaveChanges1() Implements Domain.DataSource.IDataSource.SaveChanges
    SaveChanges()
End Sub
End Class

Answer 1

答えが見つかりました。リレーションシップの「多」側のナビゲーションプロパティは、 IEnumerable（Of T）ではなく、ICollection（Of T）である必要があります。

Public Class HvacAudit
    Public Property HvacAuditID As Integer

    Public Overridable Property HvacAuditPictures As ICollection(Of HvacAuditPicture)

   ... other properties
End Class