自用的简单事件系统

众所周知，在软件开发中（尤其是大型工程里），事件系统是必不可少的，它能帮助我们解耦，使项目中的逻辑更好的分离开来，这里给出我自己的一份解决方案。

方案基于C#和ecs架构，在unity里用强烈推荐升级到2017或以上，新兼容的await语法简直是异步的福音。

首先必不可少的，事件类型的枚举

public enum MyEventType
    {
        NumericChange,
    }

监听者的基类：

    public abstract class MyeventWatcher:Component
    {
        public abstract MyEventType[] EventTypes { get; set; }

        public void Awake()
        {
            foreach(var type in EventTypes)
            {
                Game.Scene.GetComponent<MyEventWatcherComponent>().AddEvent(type, this);
            }
        }

        public abstract Task RunEvent(MyEventType eventType, params object[] param);
    }

事件的管理：

    public class MyEventWatcherComponent:Component
    {
        public static MyEventWatcherComponent Single;

        Dictionary<MyEventType, List<MyeventWatcher>> allWatchers = new Dictionary<MyEventType, List<MyeventWatcher>>();

        public void Awake()
        {
            Single = this;
        }

        public void AddEvent(MyEventType eventType, MyeventWatcher myeventWatcher)
        {
            List<MyeventWatcher> list = null;
            allWatchers.TryGetValue(eventType,out list);
            if (list == null)
            {
                list = new List<MyeventWatcher>();
                allWatchers.Add(eventType, list);
            }
            list.Add(myeventWatcher);
        }
        public void RemoveEvent(MyEventType eventType, MyeventWatcher myeventWatcher)
        {
            try
            {
                allWatchers[eventType].Remove(myeventWatcher);
            }
            catch(Exception e)
            {
                Log.Debug($"删除事件失败。
 {e}");
            }
        }
        
        public async Task RunEvent(MyEventType eventType, params object[] param)
        {
            List<MyeventWatcher> list = null;
            allWatchers.TryGetValue(eventType, out list);
            if (list == null) return;
            for (int i = 0; i < list.Count; i++)
            {
                await list[i].RunEvent(eventType,param);
            }
        }
    }

总的来说是非常简单易懂的架构，呼唤事件调用

MyEventWatcherComponent.Single.RunEvent(...)

即可，事件的监听则继承MyeventWatcher并实现相应的方法，当然，事件的参数要事先规定好，进行相应的类型转换。

一个简单的监听例子：

    public class EventWactcherSample : MyeventWatcher
    {
        public override MyEventType[] EventTypes { get; set; } = new MyEventType[] { MyEventType.NumericChange };

        public override async Task RunEvent(MyEventType eventType, params object[] param)
        {
            Log.Debug($"type:{param[0]},value:{param[1]}");
        }
    }