//引用的命名空间 using System.Runtime.InteropServices; using System.Security; //////////////////////////// /// <summary> /// 定义一个高精度的时间类 /// </summary> public class Timer { #region private members private long ticksPerSecond = 0; private long elapsedTime = 0; private long baseTime = 0; #endregion #region windows API /// <summary> /// 获取时间的精度 /// </summary> /// <param name="PerformanceFrequency"></param> /// <returns></returns> [SuppressUnmanagedCodeSecurity] [DllImport("kernel32")] static private extern bool QueryPerformanceFrequency(ref long PerformanceFrequency); /// <summary> /// 获取时间计数 /// </summary> /// <param name="PerformanceCount"></param> /// <returns></returns> [SuppressUnmanagedCodeSecurity] [DllImport("kernel32")] static private extern bool QueryPerformanceCounter(ref long PerformanceCount); #endregion #region constructors /// <summary> /// new /// </summary> public Timer() { // Use QueryPerformanceFrequency to get frequency of the timer if (!QueryPerformanceFrequency(ref ticksPerSecond)) throw new ApplicationException("Timer: Performance Frequency Unavailable"); Reset(); } #endregion #region public methods /// <summary> /// 重置时间相关计数器 /// </summary> public void Reset() { long time = 0; QueryPerformanceCounter(ref time); baseTime = time; elapsedTime = 0; } /// <summary> /// 获取当前与最近一次 reset 时间差 /// </summary> /// <returns>The time since last reset.</returns> public double GetTime() { long time = 0; QueryPerformanceCounter(ref time); return (double)(time - baseTime) / (double)ticksPerSecond; } /// <summary> /// 获取当前系统的时间 ticks 数 /// </summary> /// <returns>The current time in seconds.</returns> public double GetAbsoluteTime() { long time = 0; QueryPerformanceCounter(ref time); return (double)time / (double)ticksPerSecond; } /// <summary> /// 获取此次与上次调用此方法的两次时间差 /// </summary> /// <returns>The number of seconds since last call of this function.</returns> public double GetElapsedTime() { long time = 0; QueryPerformanceCounter(ref time); double absoluteTime = (double)(time - elapsedTime) / (double)ticksPerSecond; elapsedTime = time; return absoluteTime; } #endregion }