如果取出绑定到事件的方法数量

 // 事件访问器的定义
int eventCount=0;
    public event EventHandler NumberChanged {
        add {
    eventCount++;
            numberChanged = value;
        }
        remove {
     eventCount--;
            numberChanged -= value;
        }
    }

或取委托数组
public event EventHandler NumberChanged;
//某个方法内
Delegate[] delegates = NumberChanged.GetInvocationList();