当有很多事件，大多数事件不会实现时，可以使用字典存储事件实例，这也是事件选择器的典型用法。

public delegate void EventHandler1(int i);    public delegate void EventHandler2(string s);    public class PropertyEvent    {        Dictionary
     
       eventTable;        public PropertyEvent()        {            eventTable = new Dictionary
      
       ();            eventTable.Add("Event1", null);            eventTable.Add("Event2", null);        }        public event EventHandler1 Event1        {            add            {                lock (eventTable)                {                    eventTable["Event1"] = (EventHandler1)eventTable["Event1"] + value;                }            }            remove            {                lock (eventTable)                {                    eventTable["Event1"] = (EventHandler1)eventTable["Event1"] - value;                }            }        }        public event EventHandler2 Event2        {            add            {                lock (eventTable)                {                    eventTable["Event2"] = (EventHandler2)eventTable["Event2"] + value;                }            }            remove            {                lock (eventTable)                {                    eventTable["Event2"] = (EventHandler2)eventTable["Event2"] - value;                }            }        }        public void RaiseEvent1(int i)        {            EventHandler1 handler1 = (EventHandler1)eventTable["Event1"];            if (handler1 != null)                handler1(i);        }        public void RaiseEvent2(string s)        {            EventHandler2 handler2 = (EventHandler2)eventTable["Event2"];            if (handler2 != null)                handler2(s);        }    }    class DictionaryEvent    {        public static void DelegateMethod1(int i)        {            Console.WriteLine(i.ToString());        }        public static void DelegateMethod2(string s)        {            Console.WriteLine(s);        }        public static void Main(string[] args)        {            PropertyEvent p = new PropertyEvent();            p.Event1 += DictionaryEvent.DelegateMethod1;            p.Event1 += DictionaryEvent.DelegateMethod1;            p.Event1 += DictionaryEvent.DelegateMethod1;            p.Event1 -= DictionaryEvent.DelegateMethod1;            p.RaiseEvent1(1);            p.Event2 += DictionaryEvent.DelegateMethod2;            p.Event2 += DictionaryEvent.DelegateMethod2;            p.Event2 += DictionaryEvent.DelegateMethod2;            p.Event2 -= DictionaryEvent.DelegateMethod2;            p.RaiseEvent2("Test");            Console.Read();        }    }
      
     

输出如下：