window编程【1】： 取得两个FILETIME 的时间差

如果为SYSTEMTIME，可以通过SystemTimeToFileTime先转到FILETIME

 

#define NOMINMAX

#include <algorithm>
#include <windows.h>

SYSTEMTIME systemtime_difference(SYSTEMTIME const& st1, SYSTEMTIME const& st2)
{
    FILETIME ft1;
    SystemTimeToFileTime(&st1, &ft1);
    ULARGE_INTEGER const u1 = { ft1.dwLowDateTime, ft1.dwHighDateTime };

    FILETIME ft2;
    SystemTimeToFileTime(&st2, &ft2);
    ULARGE_INTEGER const u2 = { ft2.dwLowDateTime, ft2.dwHighDateTime };

    ULARGE_INTEGER u3;
    u3.QuadPart = std::max(u1.QuadPart, u2.QuadPart) - std::min(u1.QuadPart, u2.QuadPart);
    FILETIME const ft3 = { u3.LowPart, u3.HighPart };

    SYSTEMTIME st3;
    FileTimeToSystemTime(&ft3, &st3);
    // FILETIME's starting point is 1601-01-01
    st3.wYear -= 1601;
    st3.wMonth -= 1;
    st3.wDay -= 1;
    st3.wDayOfWeek = 0; // useless for this purpose, make it always 0 so it's always ignored
    return st3;
}

int main()
{
    SYSTEMTIME const st1 = { 2008, 10, 3, 15, 6, 5, 31, 12 };
    SYSTEMTIME const st2 = { 2009, 12, 0, 27, 10, 7, 59, 56 };
    SYSTEMTIME st3 = systemtime_difference(st1, st2);

    return 0;
}

感谢：

http://blog.csdn.net/sandro_zhang/article/details/7109456