消息分發機制的簡單實作

消息分發機制：

簡單來說就是你觸發了某個事件時，會把對應的消息分發下去，這個消息你可以選擇接收或者不收，代碼也不會報錯。而當你在某個代碼中注冊了這個事件的監聽，你就可以收到該事件發來的消息，但使用完要記得移除監聽。

代碼如下：

public class MyEventMsg
    {

        public delegate void DelHandler(MyMessage a);

        public static Dictionary<string, DelHandler> delHandelDic = new Dictionary<string, DelHandler>();

        /// <summary>
        /// 添加監聽
        /// </summary>
        /// <param name="eventString"></param>
        /// <param name="delHandler"></param>
        public static void AddListener(string eventString, DelHandler delHandler)
        {
            if (!delHandelDic.ContainsKey(eventString))
            {
                delHandelDic.Add(eventString, null);
            }
            delHandelDic[eventString] += delHandler;
        }

        /// <summary>
        /// 移除監聽
        /// </summary>
        /// <param name="eventString"></param>
        /// <param name="delHandler"></param>
        public static void RemoveListener(string eventString, DelHandler delHandler)
        {
            if (delHandelDic.ContainsKey(eventString))
            {
                delHandelDic[eventString] -= delHandler;
            }
        }

        public static void ClearAllListener()
        {
            if (delHandelDic != null)
                delHandelDic.Clear();
        }
        /// <summary>
        /// 消息分發
        /// </summary>
        /// <param name="eventString"></param>
        /// <param name="msg"></param>
        public static void MessageDispatch(string eventString, MyMessage msg = null)
        {
            DelHandler del;
            if (delHandelDic.TryGetValue(eventString, out del))
            {
                if (del != null)
                    del.Invoke(msg);
            }
        }
    }

    public class MyMessage
    {
        public string msg;
        public int value;

        public MyMessage()
        {

        }
        public MyMessage(string msg, int value)
        {
            this.msg = msg;
            this.value = value;
        }
    }