public class DoActions
        {
            public void Doing(int i)
            { 
                Thread.Sleep(4000);
                Console.WriteLine(i.ToString());
            }
        }

        static void Main(string[] args)
        {
            for (int i = 0; i < 10; i++)
            {
                //create a Job object
                DoActions objJob = new DoActions();

                Action action = new Action(delegate()
                {
                    objJob.Doing(i);
                });
               action.BeginInvoke(null, null);
            }

            
            Console.WriteLine("Loop over.");
            Console.ReadKey();

            return;
}