class Program    {        static void Main(string[] args)        {            Run();                  }        public static async void Run()        {            var tasks = StartMultiWorkerTasks();            if (tasks.Length > 0)            {                await Task.WhenAll(tasks).ContinueWith(t =>                {                    Console.WriteLine("done ......");                });            }            Task.WaitAll(tasks);        }        /// <summary>        /// Start multi tasks        /// </summary>        /// <param name="request"></param>        /// <param name="coupleSyncResult"></param>        /// <returns></returns>        public static Task[] StartMultiWorkerTasks()        {            Task[] tasks = new Task[3];            tasks[0] = Task.Run(() => Console.WriteLine("do some thing 1...................."));            tasks[1] = Task.Run(() => Console.WriteLine("do some thing 2...................."));            tasks[2] = Task.Run(() => Console.WriteLine("do some thing 3...................."));            return tasks;        }    }