protected virtual void OnPriceChanged(PriceChangedEventArgs e) { if (PriceChanged != null) { PriceChanged(this, e); } }
static void IPhone_Changed(object sender, PriceChangedEventArgs e) { Console.WriteLine("年底大促銷,原價{0}元,現價{1}元,快來搶購啊", e.OldPrice, e.NewPrice); }