using System;

using System.Collections.Generic;

using System.Threading.Tasks;

​

namespace ConsoleApp12

{

    class FactoryToken

    {

        List<Token> ls;

        public void EnablePause()

        {

            foreach (var item in ls)

                item.EnablePause();

        }

        public void DisablePause()

        {

            foreach (var item in ls)

                item.DisablePause();

        }

        public Token Create() 

        {

            var token = new Token();

            this.ls.Add(token);

            return token;

        }

        public FactoryToken()

        {

            this.ls = new List<Token>();

        }

    }

    class Token

    {

        public void EnablePause() { pause = true; }

        public void DisablePause() { pause = false; }

        bool pause;

        public async Task Pause()

        {

            while (true)

            {

                if (pause == false) break;

               await Task.Delay(50);

            }

        }

    }

    class Program

    {

        static async Task Main(string[] args)

        {

            FactoryToken factory = new FactoryToken();

            var token = factory.Create();

            Task task = Task.Run(async() =>

            {

                await Task.Delay(10);

                for (int i = 0; i < 1999; i++)

                {

                    await token.Pause();

                    Console.WriteLine(i);

                }

            });

            factory.EnablePause();

            await Task.Delay(1000);

            factory.DisablePause();

           // await Task.Delay(1000);

            Console.WriteLine("OK");

        }

    }

}

​