class Program

    {

        static void Main(string[] args)

        {

            //PaintBody();

            //PaintBodyAsync();

            Console.WriteLine("End");

        }    

 static async Task PaintBodyAsync()

        {

            Console.WriteLine("Header");

            //就是遇到awaIt,这里面的东西不会阻塞，继续执行

            await Task.Run(() =>

            {

                //System.Threading.Thread.Sleep(1000);//线程不管是否睡眠，都是先执行其他方法

                Console.WriteLine("Body");

            });

            Console.WriteLine("Footer");

        }

        static void PaintBody()

        {

            Console.WriteLine("Header");

            System.Threading.Thread.Sleep(1000);

            Console.WriteLine("Body");

            Console.WriteLine("Footer");

        }

    }