time_t和SYSTEMTIME之间的相互转换

#include <ctime>

/*

**time_t转SYSTEMTIME

*/

SYSTEMTIME TimetToSystemTime(time_t t)

{

FILETIME ft;

SYSTEMTIME pst;

LONGLONG nLL = Int32x32To64(t, 10000000) + 116444736000000000;

ft.dwLowDateTime = (DWORD)nLL;

ft.dwHighDateTime = (DWORD)(nLL >> 32);

FileTimeToSystemTime(&ft, &pst);

return pst;

}

/*

**SYSTEMTIME转time_t

*/

time_t SystemTimeToTimet(SYSTEMTIME st)

{

FILETIME ft;

SystemTimeToFileTime( &st, &ft );

LONGLONG nLL;

ULARGE_INTEGER ui;

ui.LowPart = ft.dwLowDateTime;

ui.HighPart = ft.dwHighDateTime;

nLL = (ft.dwHighDateTime << 32) + ft.dwLowDateTime;

time_t pt = (long)((LONGLONG)(ui.QuadPart - 116444736000000000) / 10000000);

return pt;

}

/*

**time_t转SYSTEMTIME

*/

SYSTEMTIME Time_tToSystemTime(time_t t)

{

tm temptm = *localtime(&t);

SYSTEMTIME st = {1900 + temptm.tm_year,

1 + temptm.tm_mon,

temptm.tm_wday,

temptm.tm_mday,

temptm.tm_hour,

temptm.tm_min,

temptm.tm_sec,

0};

return st;

}

/*

**SYSTEMTIME转time_t

*/

time_t SystemTimeToTime_t( const SYSTEMTIME& st )

{

tm temptm = {st.wSecond,

st.wMinute,

st.wHour,

st.wDay,

st.wMonth - 1,

st.wYear - 1900,

st.wDayOfWeek,

0,

0};

return mktime(&temptm);

}