public void Press_operator()
{
var ui = new UI();
ui.Operator_pressed += req =>
{
var opnum = (int) req.Item1[0];
ui.Display_result(new Tuple<IEnumerable<int>, int>(new[]{opnum}, req.Item2));
};
ui.ShowDialog();
}
public void Enter_number_and_display_stack()
{
var ui = new UI();
var list = new List<int>();
ui.Number_entered += n =>
{
list.Add(n);
ui.Display_result(new Tuple<IEnumerable<int>, int>(list, n*10));
};
ui.ShowDialog();
}