事件模式实现通知

class LoggerClass
    {
    }
    public class LoggerEventArgs : EventArgs
    {
        public string Message { get; private set; }
        public int Priority { get; private set; }
        public LoggerEventArgs(int priority,string  msg)
        {
            Priority = priority;
            Message = msg;
        
        }
    
    }
    public static  struct LogerEventName
    {
        public static readonly string OnError = "OnError";
        public static readonly string OnFail = "OnFail";
        public static readonly string OnWaring = "OnWaring";

    }

    public sealed class Logger
    {
        private static Dictionary<string, EventHandler<LoggerEventArgs>> Handers = new Dictionary<string, EventHandler<LoggerEventArgs>>();
        public static void AddLoger(string system,EventHandler<LoggerEventArgs> ev)
        {
            if (Handers.ContainsKey(system))
            {
                Handers[system] += ev;
            }
            else
            {
                Handers.Add(system,ev);
            }
        }
        public static void RemoveLogger(string system,EventHandler<LoggerEventArgs> ev)
        { 
           if (Handers.ContainsKey(system))
            {
                Handers[system] -= ev;
            }
        }

        public static void AddMsg(string sytem,int priority,string msg)
        {
            if (string.IsNullOrEmpty(sytem) || !Handers.ContainsKey(sytem))
             return;
            LoggerEventArgs args = new LoggerEventArgs(priority,msg);
            EventHandler<LoggerEventArgs> eventthander = null;
            Handers.TryGetValue(sytem, out eventthander);
            if (eventthander != null)
                eventthander(null, args);
        }
    }