C# 计算程序的运行时间

//用Stopwatch类(System.Diagnostics)计算耗时
static void SubTest() 
{ 
Stopwatch sw = new Stopwatch(); 
sw.Start();

//耗时巨大的代码

sw.Stop(); 
TimeSpan ts2 = sw.Elapsed; 
Console.WriteLine("Stopwatch总共花费{0}ms.", ts2.TotalMilliseconds); 
}