using System;

using System.Threading;

using System.Threading.Tasks;

using System.Threading.Channels;

​

public class Program

{

    private static readonly Channel<bool> _channel = Channel.CreateBounded<bool>(new BoundedChannelOptions(1)

    {

        SingleReader = false,

        SingleWriter = true,

        FullMode = BoundedChannelFullMode.DropWrite,

    });

    public static void Main()

    {

        Task.Run(WaitBeforeComplete);

        // sleep for a while

        Thread.Sleep(3000);

        Console.WriteLine("signal");

        // complete the channel

        _channel.Writer.Complete();

        for( int i = 0; i < 100; i++){

            Task.Run(WaitAfterComplete);

        }

    }

    static async Task WaitBeforeComplete(){

        await _channel.Reader.WaitToReadAsync().ConfigureAwait(false);

        Console.WriteLine("WaitBeforeComplete exits");

    }

    static async Task WaitAfterComplete(){

        await _channel.Reader.WaitToReadAsync().ConfigureAwait(false);

        Console.WriteLine("WaitAfterComplete exits");

    }

}