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我想知道在 C++ 中测量某些代码的执行时间的最佳方法是什么。是否有任何内置的秒表（.Net）类？我正在 VS2010 上开发 C++。我如何（如果）在我的 C++ 项目中使用 .Net 库？先感谢您。

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4 回答 4

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AFAIK C++ 没有像.NET 中的秒表这样的标准类。

http://cplus.about.com/od/howtodothingsi2/a/timing.htm是 Windows 平台上高分辨率计时器的示例。

这种计时器的平台独立实现是：http: //www.boost.org/libs/timer/doc/index.html

高温高压

于 2012-02-06T14:14:38.410 回答
2

您可能会考虑http://code.google.com/p/cpp-stopwatch，它是纯 C++ 语言，没有依赖关系，并带有一个方便的 Visual Studio 解决方案。哦，我写了。

于 2012-06-20T09:28:42.447 回答
1

您可以使用 QueryPerformanceCounter 在“分析”某些代码时获得更好的时机（它并不完美，但应该足以让您入门）。

BOOL WINAPI QueryPerformanceCounter( __out  LARGE_INTEGER *lpPerformanceCount );

http://msdn.microsoft.com/en-us/library/windows/desktop/ms644904(v=vs.85).aspx。

于 2012-02-06T15:49:10.967 回答
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值得一提的是，这是一个 Windows 实现（非常类似于 .NET）：

class Stopwatch
{
    LARGE_INTEGER _startTime;
    LARGE_INTEGER _frequency;

public:
    Stopwatch(bool start = false) :_startTime({ 0 })
    {
        QueryPerformanceFrequency(&_frequency);
        if (start)
        {
            Start();
        }
    }

    LONGLONG GetStartTime() { return _startTime.QuadPart; }
    bool IsStarted() { return _startTime.QuadPart; }
    bool IsStopped() { return !IsStarted(); }

    void Start()
    {
        QueryPerformanceCounter(&_startTime);
    }

    void Stop()
    {
        ZeroMemory(&_startTime, sizeof(LARGE_INTEGER));
    }

    static LONGLONG GetFrequency()
    {
        LARGE_INTEGER li;
        QueryPerformanceFrequency(&li);
        return li.QuadPart;
    }

    static LONGLONG GetTicks()
    {
        LARGE_INTEGER endingTime;
        QueryPerformanceCounter(&endingTime);
        return endingTime.QuadPart;
    }

    LONGLONG GetElapsedTicks(bool restart = false)
    {
        LARGE_INTEGER endingTime;
        QueryPerformanceCounter(&endingTime);
        auto qp = endingTime.QuadPart - _startTime.QuadPart;
        if (restart)
        {
            Start();
        }
        return qp;
    }

    LONGLONG GetElapsed100NanoSeconds(bool restart = false)
    {
        LARGE_INTEGER endingTime;
        QueryPerformanceCounter(&endingTime);

        LARGE_INTEGER elapsed100NanoSeconds{};
        elapsed100NanoSeconds.QuadPart = endingTime.QuadPart - _startTime.QuadPart;
        elapsed100NanoSeconds.QuadPart *= 10000000;
        elapsed100NanoSeconds.QuadPart /= _frequency.QuadPart;
        if (restart)
        {
            Start();
        }
        return elapsed100NanoSeconds.QuadPart;
    }

    LONGLONG GetElapsedMicroseconds(bool restart = false)
    {
        LARGE_INTEGER endingTime;
        QueryPerformanceCounter(&endingTime);

        LARGE_INTEGER elapsedMicroSeconds{};
        elapsedMicroSeconds.QuadPart = endingTime.QuadPart - _startTime.QuadPart;
        elapsedMicroSeconds.QuadPart *= 1000000;
        elapsedMicroSeconds.QuadPart /= _frequency.QuadPart;
        if (restart)
        {
            Start();
        }
        return elapsedMicroSeconds.QuadPart;
    }

    LONGLONG GetElapsedMilliseconds(bool restart = false)
    {
        LARGE_INTEGER endingTime;
        QueryPerformanceCounter(&endingTime);

        LARGE_INTEGER elapsedMilliSeconds{};
        elapsedMilliSeconds.QuadPart = endingTime.QuadPart - _startTime.QuadPart;
        elapsedMilliSeconds.QuadPart *= 1000;
        elapsedMilliSeconds.QuadPart /= _frequency.QuadPart;
        if (restart)
        {
            Start();
        }
        return elapsedMilliSeconds.QuadPart;
    }

    LONGLONG GetElapsedSeconds(bool restart = false)
    {
        LARGE_INTEGER endingTime;
        QueryPerformanceCounter(&endingTime);

        LARGE_INTEGER elapsedSeconds{};
        elapsedSeconds.QuadPart = endingTime.QuadPart - _startTime.QuadPart;
        elapsedSeconds.QuadPart /= _frequency.QuadPart;
        if (restart)
        {
            Start();
        }
        return elapsedSeconds.QuadPart;
    }
};
于 2021-06-10T16:41:39.337 回答