计算代码段运行时间

            //建立计时器1
            System.Diagnostics.Stopwatch sw1 = new System.Diagnostics.Stopwatch();
            sw1.Start();
         

            for (int i = 0; i < 1500000; i++)
            {
                //执行的代码段，用for循环放大观察
            }


            sw1.Stop();

            TimeSpan ts1 = sw1.Elapsed;
            Console.WriteLine(" time1 {0}", ts1.TotalMilliseconds);