//显示器方法
public void ShowMsg(object sender, Heater.BoilEventArgs e)
{
Heater heater = (Heater)sender;
//访问heater类中属性
Console.WriteLine("显示器:热水器的产地：{0}", heater.area);
Console.WriteLine("显示器:热水器的型号：{0}", heater.type);
Console.WriteLine("显示器:热水器当前温度：{0}", e.temperature);
}
static void Main(string[] args)
{
Heater heater = new Heater();
Alarm alarm = new Alarm();
Display display = new Display();
//注册方法
heater.Boil+= alarm.MakeAlert;
heater.Boil += display.ShowMsg;
Console.WriteLine("开始执行");
heater.BoilWater();
Console.Read();
}