Namespace DataAccess
 
    Public Class Tournament
        Inherits IObservable
 
#Region " members "
 
        ''' <summary>
        ''' Singleton-Instanz.
        ''' </summary>
        ''' <remarks></remarks>
        Private Shared myInstance As Tournament
 
        '''' <summary>
        '''' Strongly Typed TableAdapter, um Abfragen durch Pufferung zu _
          reduzieren.
        '''' </summary>
        '''' <remarks></remarks>
        Private myDT As GDA.TournamentDataTable
 
        ' Erbt die Liste von IObservable (wird im Konstruktor instanziiert)
#End Region
[...]
  Public Function GetAll() As GDA.TournamentDataTable
            Return myDT
   End Function
[...]
 
Public Sub UpdateData(ByVal dt As GDA.TournamentDataTable)
 
            Dim ta As New GDATableAdapters.TournamentTableAdapter()
 
            ' Versuch, die Daten zu persistieren mit "second chance" bei 
            ' Problemen
            Try
                ta.Update(dt) <-- Fehler!!!
                dt.AcceptChanges()

Public Class TournamentEdit
    Implements DataAccess.IObserver
 
#Region " members "
 
    [...]
    Private myTournament As DataAccess.Tournament
[...]
Private Sub DeleteTournament()
        If Not myTournament.Contains(myTournamentId) Then
            Return
        Else
            Dim result As DialogResult
            Dim dt As GDA.TournamentDataTable
            dt = myTournament.GetAll
            Dim dr As GDA.TournamentRow = myTournament.GetSingle(myTournamentId)
            If [Sicherheitabfrage-bestätigt] Then
                dr.Delete()
                Try
                    myTournament.UpdateData(dt)
                Catch ex As Exception
                    Debug.WriteLine(ex.Message & " " & ex.StackTrace)
                End Try
[...]