线程池

 class Program
    {
        static void Main(string[] args)
        {
            {
                //线程池初识
                //Console.WriteLine("Main:");
                //ThreadPool.QueueUserWorkItem(s =>
                //{
                //    Console.WriteLine("this is treadpool :" + s);
                //}, 100);
                //Thread.Sleep(1);
                //Console.WriteLine("hello world");
            }
            {
                //执行上下文
                ////将数据放置Main函数逻辑调用上下文中
                //CallContext.LogicalSetData("name", "wjire");
                ////阻止“流向”之前（可以获得逻辑调用上下文数据）
                //ThreadPool.QueueUserWorkItem(s =>
                //{
                //    Console.WriteLine($"name={CallContext.LogicalGetData("name")}");
                //});
                ////阻止“流向”
                //ExecutionContext.SuppressFlow();

                ////阻止“流向”之后（不可获得逻辑调用上下文数据）
                //ThreadPool.QueueUserWorkItem(s =>
                //{
                //    Console.WriteLine($"name={CallContext.LogicalGetData("name")}");
                //});
                ////恢复“流向”
                //ExecutionContext.RestoreFlow();
            }
            {
                //取消操作
                CancellationTokenSource cts = new CancellationTokenSource();
                //线程取消时,执行的回调方法.
                //1.0后登记的先执行.
                //2.0如果cancel()方法没法有入参,则默认是false,这种情况下,所有的回调方法都会执行,最终统一抛出一个异常.
                //3.0如果cancel()方法入参是true,则抛出异常的回调方法会阻止后续的回调方法的执行.
                var r1 = cts.Token.Register(() =>
                 {
                     Console.WriteLine("1");
                 });

                var r2 = cts.Token.Register(() =>
                 {
                     Thread.Sleep(2000);
                     Console.WriteLine("2");
                     throw new Exception("this is 2 exception");
                 });
                ThreadPool.QueueUserWorkItem(s =>
                {
                    for (int i = 0; i < 10000; i++)
                    {
                        if (cts.Token.IsCancellationRequested)
                        {
                            Console.WriteLine("the thread is cancel");
                            break;
                        }
                        Console.WriteLine("i={0}", i);
                        Thread.Sleep(1000);
                    }
                });
                //删除已登记的回调方法.
                //r2.Dispose();

                //3秒钟之后自动取消
                //cts.CancelAfter(3000);
                Console.ReadKey();
                cts.Cancel();
            }

            Console.Read();
        }
    }