public static ThreadSafeLoggerSingleton GetInstance()
 {
     lock (locker)
     {
         if (_loggerInstance == null)
         {
             _loggerInstance = new ThreadSafeLoggerSingleton();
         }
     }
     return(_loggerInstance);
 }
        static void Main(string[] args)
        {
            DoHardWork doHardWork = new DoHardWork();

            LoggerSingelton.GetInstance().Log("Start easy work !");
            doHardWork.EasyWork();
            LoggerSingelton.GetInstance().Log("Start hard work !");
            doHardWork.HardWork();
            ThreadSafeLoggerSingleton.GetInstance().Log("Thread Safe Logger !");
            Console.ReadKey();
        }