C#：程序控制--计算程序执行耗费的时间

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;

namespace watch
{
class Program
{
static void Main(string[] args)
{
Stopwatch sw = new Stopwatch();
Console.WriteLine("开始计时");
sw.Start();

int s = 0;
for (int i = 0; i < 10000000; i++)
{
s += i;
}
sw.Stop();
Console.WriteLine("执行完毕,停止计时.程序执行耗时{0}毫秒", sw.ElapsedMilliseconds);
}
}
}