private void buttonDelete_Click(object sender, EventArgs e) { int index = listBoxNumber.SelectedIndex; try { nc.deleteNumber(index); listBoxNumber.DataSource = null; listBoxNumber.DataSource = nc.getNumbers(); if (listBoxNumber.Items.Count == 0) { textBoxNumber.Text = string.Empty; eltakarPaneleket(); } } catch (ControllerException ce) { errorProviderAdd.SetError(buttonDelete, ce.Message); } catch (Exception ex) { Debug.WriteLine(ex.Message); } }