Public Shared Function db_pfad_from_fileopendlg() As String
        Dim openfd As New System.Windows.Forms.OpenFileDialog
 
        With openfd
            .Title = "Datenbank auswählen"
            .Filter = "Access Datenbank (*.mdb)|*.mdb"
            .Multiselect = False
        End With
        Dim result As DialogResult = openfd.ShowDialog()
        Dim my_db_path As String
        If result = Windows.Forms.DialogResult.OK Then
            my_db_path = openfd.FileName
            Dim db_path_from_reg As String = My.Settings.db_path.ToString
            If Not String.IsNullOrEmpty(db_path_from_reg) Then
                If Not my_db_path = db_path_from_reg.ToString Then
                   'irgendein Codefragment
                End If
                Return my_db_path
            Else
                Return my_db_path
            End If
        Else
            my_db_path = String.Empty
            Return my_db_path
        End If
    End Function

Dim db_path As String = Class_main.db_pfad_from_fileopendlg()
        conn_para.db_path = db_path
        conn_para.full_mode = True

Protected Friend conn_para As New Class_main