'''<summary>
        '''Prüft ob die erhalten Antwort von GetResponse gültig ist.
        '''</summary>
        '''<param name="Response">Antort von GetResponse</param>
        Private Sub CheckResponse(ByVal Response As String)
 
            If Not String.Compare(Response.Substring(0, 3), _
              Commands.ServerConfirm, False, _
              Globalization.CultureInfo.CurrentCulture) = 0 Then
                Me.Client.Close()
                Me.Connected = False
                Throw New ApplicationException("Response " + Response + " not" & _
                  "expected.")
            End If
 
        End Sub
 
        '''<summary>
        '''Gibt eine List(of POP3Message) der verfügbaren Nachrichten zurück.
        '''</summary>
        Public Function GetMessageList() As List(Of MessageList)
 
            If Me.Connected = False Then
                Throw New InvalidOperationException("Not connected!")
            End If
            Dim Pop3l As New List(Of MessageList)
            Me.Send(Commands.List)
            Dim Response() As String = Me.GetResponse.Split(vbCrLf)
            CheckResponse(Response(0))
 
            For i As Integer = 1 To Response.Length - 3
                Dim POP3m As New MessageList
                POP3m.ID = i
                POP3m.Size = Convert.ToInt64(Response(i).Split(" ")(1))
                Pop3l.Add(POP3m)
            Next
 
            Return Pop3l
 
        End Function
 
        '''<summary>
        '''Nachricht mit angebener Nummer vom Server lesen
        '''</summary>
        '''<param name="MessageID">MessageID</param>
        Public Function GetMessage(ByVal MessageID As Integer) As String
 
            If Me.Connected = False Then
                Throw New InvalidOperationException("Not connected!")
            End If
            Me.Send(Commands.GetMessage & MessageID)
            Me.CheckResponse(Me.GetResponse)
            Dim Response As String = Me.GetResponse
            Return Response
 
        End Function
 
    End Class
End Namespace