C#使用记秒表检查程序运行时间

如果你担忧某些代码非常耗费时间，可以用StopWatch来检查这段代码消耗的时间，如下面的代码所示

System.Diagnostics.Stopwatch timer = new System.Diagnostics.Stopwatch();
timer.Start();
Decimal total = 0;
int limit = 1000000;
for (int i = 0; i < limit; ++i)
{
  total = total + (Decimal)Math.Sqrt(i);
}
timer.Stop();
Console.WriteLine(“Sum of sqrts: {0}”,total);
Console.WriteLine(“Elapsed milliseconds: {0}”,timer.ElapsedMilliseconds);
Console.WriteLine(“Elapsed time: {0}”,timer.Elapsed);

class AutoStopwatch : System.Diagnostics.Stopwatch,IDisposable
{
   public AutoStopwatch()
   { 
     Start();
   }
   public void Dispose()
   {
     Stop();
     Console.WriteLine(“Elapsed: {0}”,this.Elapsed);
   }
}

借助于using语法，像下面的代码所示，可以检查一段代码的运行时间，并打印在控制台上。

using (new AutoStopwatch())
{
  Decimal total2 = 0;
  int limit2 = 1000000;
  for (int i = 0; i < limit2; ++i)
  {
     total2 = total2 + (Decimal)Math.Sqrt(i);
  }
}