Public MustInherit Class dbiObjCollection : Inherits _
  System.Collections.CollectionBase
    Public MustOverride Function ReceiveChanges(ByVal myChange As _
    clsDatabaseChanges)
    Public MustOverride Sub DoUpdate()
    Public MustOverride ReadOnly Property Data() As Collection
    Public Event HasChanges()
End Class

Public Class collectionContries : Inherits dbiObjCollection
 
#Region "Interne Deklarationen"
    Private _contriesCollection As New Collection()
    Private _contriesCollectionChanges As New Collection()
    Private _collectionTypeName As String = "clsContries"
    Public Shadows Event HasChanges()
#End Region
 
#Region "Konstruktoren"
 
   ' Lese alle Objekte aus der Datenbank und füge sie in die Collection
 
    Public Sub New()
      ...
    End Sub
 
#End Region
 
#Region "Eigenschaften"
 
   ...
#End Region
 
#Region "Methoden und Funktionen"
 
 
   ' Suche ein Element in der Collection und liefere Referenz zurück
    Public Function GetItemRef(ByVal myContryID As Integer) As clsContries
        Return _contriesCollection.Item(myContryID.ToString)
    End Function
 
 
   ' Empfängt Änderungen in der Collection und fügt sie in die Warteschlange ein
    Public Overrides Function ReceiveChanges(ByVal myChanges As _
      clsDatabaseChanges)
        _contriesCollectionChanges.Add(myChanges, myChanges.FilterString & ":" _
        & myChanges.RowAction)
    End Function
 
   ' Arbeitet die in der Warteschlange befindlichen Änderungen ein 
    Public Overrides Sub DoUpdate()
        Dim currChange As clsDatabaseChanges
        Dim hasChangesFlag As Boolean = False
        For Each currChange In _contriesCollectionChanges
             Dim pkArray() As String
            pkArray = currChange.FilterString.Replace("AND", ";").Split(";")
            Dim _contryID As Integer = pkArray(0).Trim.Substring(pkArray( _
              0).Trim.IndexOf("=") + 1)
            Select Case currChange.RowAction
                Case "update"
                    CType(_contriesCollection.Item(_contryID.ToString), _
                      clsContries).UpdateFromDb()
                Case "insert"
                    Try
                        Dim newContries As New clsContries(_contryID, True)
                        _contriesCollection.Add(newContries, _contryID.ToString)
                    Catch
                    End Try
                Case "delete"
                    _contriesCollection.Remove(_contryID.ToString)
            End Select
            _contriesCollectionChanges.Remove(currChange.FilterString & ":" & _
              currChange.RowAction)
            hasChangesFlag = True
        Next
        If hasChangesFlag Then
            RaiseEvent HasChanges()
        End If
    End Sub
 
   ' Fügt ein dbiObjekt in die Collection und die Datenbank ein
 
    Public Sub AddItem(ByVal myContryName As String)
    Dim tmpContries As New clsContries(myContryName)
        _contriesCollection.Add(tmpContries,tmpContries.ContryID.ToString)
    End Sub
 
#End Region
 
End Class 'collectionContries