利用EventHandler系统委托，触发Event

//注册
boli.BoliWaterEvent += boli1.Alarm;
boli.BoliWaterEvent += boli1.Alarm1;
//执行
boli.Boliwater();

using System;

namespace DelegateEventObserver
{
    class Program
    {
        static void Main(string[] args)
        {
            a boli = new a();
            b boli1 = new b();
            boli.BoliWaterEvent += boli1.Alarm;
            boli.BoliWaterEvent += boli1.Alarm1;
            boli.Boliwater();
            Console.ReadKey();
        }
    }
    class BoliEventAgrs : EventArgs//继承系统事件参数接口
    {
        public readonly int tem;
        public BoliEventAgrs(int tem)
        {
            this.tem = tem;
        }
    }
    class a
    {
        //public delegate void Boli(object sender,BoliEventAgrs e);
        public event EventHandler<BoliEventAgrs> BoliWaterEvent;//BoliEventAgrs 为委托参数
        public void Boliwater()
        {
            for (int i=0; i<100;i++)
            {
                if (i>90)
                {
                    BoliEventAgrs e = new BoliEventAgrs(i);
                    if (BoliWaterEvent != null)
                    {
                        BoliWaterEvent(this, e);
                    }
                }
            }
        }
    }
    /// <summary>
    /// 委托方法，事件注册方法，参数e为 控制温度
    /// </summary>
    class b
    {
        public void Alarm(object sender,BoliEventAgrs e)
        {
            if (e.tem>95)
            {
                Console.WriteLine("水温{0}",e.tem);
            }
        }
        public void Alarm1(object sender, BoliEventAgrs e)
        {
            if (e.tem >98)
            {
                Console.WriteLine("水温{0},马上开啦", e.tem);
            }
        }
    }
}