Private Sub ComboBox2_SelectedIndexChanged(ByVal sender As System.Object, ByVal _
  e As System.EventArgs) Handles ComboBox2.SelectedIndexChanged
    Dim DBdatareader As OleDbDataReader
    Dim DB As OleDbConnection
    Dim DBcomando As OleDbCommand
    Dim dbFile As String
    Dim strCmd As String
 
 
        dbFile = "C:\temp\Schueler.accdb"
        DB = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data" & _
          "Source=" + _
                dbFile + ";Persist Security Info=False;")
        DB.Open()
        Nationalitaet = ComboBox2.SelectedItem.ToString()
 
         strCmd = "select * from Schueler where Name"
 
        DBcomando = New OleDbCommand(strCmd, DB)
        DBdatareader = DBcomando.ExecuteReader()
        DBcomando = Nothing
        DBdatareader.Read()
 
        Try
            Do While DBdatareader.Read()
                SchuelerName = (DBdatareader.Item("Name").ToString)
                ListBox1.Items.Add(SchuelerName)
            Loop
        Catch ex As Exception
        End Try
        Label8.Text = Nationalitaet    End Sub