使用 c++ 在 windows 上定时执行一个函数的示例代码

#include <iostream>
#include <Windows.h>
#include <thread>
#pragma comment( lib, "Winmm" )
static int counter = 0;
static int64_t ticks_per_second;
void __stdcall on_timer(HWND h, UINT ui, UINT_PTR up, DWORD dw)
{
    std::cout << "time out, counter=" << counter << std::endl;
    counter = 0;
}
void get_message_trd_func()
{
    SetTimer(NULL, 0, 1000, on_timer);
    MSG msg;
    while (GetMessageA(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessageA(&msg);
    }
}
int main()
{
    std::cout << "go!" << std::endl;
    timeBeginPeriod(1);
    QueryPerformanceFrequency((LARGE_INTEGER*)&ticks_per_second);
    const double expected = 1.0 / 60.0;
    const int64_t expected_ticks = (int64_t)(expected * ticks_per_second);
    std::thread thr(get_message_trd_func);
    for (;;)
    {
        int64_t before_ticks = 0;
        QueryPerformanceCounter((LARGE_INTEGER*)&before_ticks);
        // do something...
        for (int i = 0; i < 10000; i++)
        {
            float a = i * i + i + sin(i) + sqrt(i);
        }
        int64_t after_ticks = 0;
        QueryPerformanceCounter((LARGE_INTEGER*)&after_ticks);
        counter++;
        int64_t ticks_need_sleep = expected_ticks - (after_ticks - before_ticks);
        double ms_need_sleep = (double)ticks_need_sleep / ticks_per_second * 1000.0;
        if (ms_need_sleep >= 1.0)
            Sleep((DWORD)ms_need_sleep);
        else
            continue;
    }
}

time out, counter=59
time out, counter=59
time out, counter=60
time out, counter=59
time out, counter=58
time out, counter=60

time out, counter=33
time out, counter=31
time out, counter=32
time out, counter=31