c# 三種計算程序運行時間的方法

第一種：
利用 System.DateTime.Now

// example1: System.DateTime.Now method DateTime 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);

 

第二種
利用Stopwatch

// example2: Stopwatch class System.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);

 

第三種
利用c++ API

// example3： c++ API long 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);

 

測試結果：
example1 time 2001.486
example2 time 2000.6587
example3 time 2.00032488719712

二三兩種方法結果比較准確