Ví dụ

CancellationTokenSourceExample.cs

        CancellationTokenSource source = null;
        void Run()
        {
            if(source?.IsCancellationRequested != false)//true hoặc source null
            {
                source?.Dispose();
                source = new CancellationTokenSource();
            }

            Task.Run(() =>
            {
                try
                {
                    using CancellationTokenSource source2 = new CancellationTokenSource();
                    using var reg = source.Token.Register(() => source2.Cancel());//xài Register khi cần trigger source2

                    while (!source2.IsCancellationRequested)//không exception
                    {
                        source2.Token.ThrowIfCancellationRequested();//throw exception

                        Task.Delay(1000, source2.Token).Wait();//throw exception

                        using Stream stream1 = new MemoryStream();
                        using Stream stream2 = new MemoryStream();
                        stream1.CopyToAsync(stream2, source2.Token).Wait();//throw exception
                    }

                    Process process = null;
                    using var reg2 = source.Token.Register(() => process.Kill());//xài Register khi cần kill process;
                    process.WaitForExit();
                }
                catch(OperationCanceledException oce)
                {
                    Console.WriteLine("Bị cancel");
                }
            });
        }
        void Cancel()
        {
            source?.Cancel();
        }