三种计算c#程序运行时间的方法

第一种：

利用 System.DateTime.Now

// example1: System.DateTime.Now methodDateTime dt1 = System.DateTime.Now;System.Threading.Thread.Sleep(time_cap);DateTime dt2 = System.DateTime.Now;TimeSpan ts = dt2.Subtract(dt1);Console.WriteLine("example1 time {0}", ts.TotalMilliseconds);

 

第二种

利用Stopwatch

// example2: Stopwatch classSystem.Diagnostics.Stopwatch sw = new System.Diagnostics.Stopwatch();sw.Start();System.Threading.Thread.Sleep(time_cap);sw.Stop();TimeSpan ts2 = sw.Elapsed;Console.WriteLine("example2 time {0}", ts2.TotalMilliseconds);

 

第三种

利用c++ API

// example3： c++ APIlong count1 = 0;long count2 = 0;long freq = 0;double result = 0;QueryPerformanceFrequency(ref freq);QueryPerformanceCounter(ref count1);System.Threading.Thread.Sleep(time_cap);QueryPerformanceCounter(ref count2);result = (double)(count2 - count1) / (double)freq;Console.WriteLine("example3 time {0}", result);

 

测试结果：

example1 time 2001.486

example2 time 2000.6587

example3 time 2.00032488719712

二三两种方法结果比较准确