private void onDeleteButtonClick(object sender, EventArgs e) { if (listView.SelectedItems.Count == 0) { MessageBox.Show("Please select item(s) to delete.", "Check your actions"); return; } if (MessageBox.Show("Are you sure you want to proceed ?", "Delete item(s)", MessageBoxButtons.YesNo, MessageBoxIcon.Question, MessageBoxDefaultButton.Button1) != DialogResult.Yes) { return; } for (var i = 0; i < listView.SelectedItems.Count; i++) { var isValid = long.TryParse(listView.SelectedItems[i].Text, out var colId); if (!isValid) { continue; } collectionRepository.deleteById(colId); } refresh(); }