如何用win32 API转换时区？

Question

我有日期字符串,如2009-02-28 15:40:05 AEDST,并希望将其转换为SYSTEMTIME结构.到目前为止,我有:

SYSTEMTIME st;
FILETIME ft;
SecureZeroMemory(&st, sizeof(st));
sscanf_s(contents, "%u-%u-%u %u:%u:%u",
    &st.wYear,
    &st.wMonth,
    &st.wDay,
    &st.wHour,
    &st.wMinute,
    &st.wSecond);
// Timezone correction
SystemTimeToFileTime(&st,  &ft);
LocalFileTimeToFileTime(&ft, &ft);
FileTimeToSystemTime(&ft, &st);

但是我的当地时区不是AEDST.所以我需要能够在转换为UTC时指定时区.

Answer 1

看看这个:

https://web.archive.org/web/20140205072348/http://weseetips.com:80/2008/05/28/how-to-convert-local-system-time-to-utc-or-gmt/

 // Get the local system time.
 SYSTEMTIME LocalTime = { 0 };
 GetSystemTime( &LocalTime );

 // Get the timezone info.
 TIME_ZONE_INFORMATION TimeZoneInfo;
 GetTimeZoneInformation( &TimeZoneInfo );

 // Convert local time to UTC.
 SYSTEMTIME GmtTime = { 0 };
 TzSpecificLocalTimeToSystemTime( &TimeZoneInfo,
                                  &LocalTime,
                                  &GmtTime );

 // GMT = LocalTime + TimeZoneInfo.Bias
 // TimeZoneInfo.Bias is the difference between local time
 // and GMT in minutes. 

 // Local time expressed in terms of GMT bias.
 float TimeZoneDifference = -( float(TimeZoneInfo.Bias) / 60 );
 CString csLocalTimeInGmt;
 csLocalTimeInGmt.Format( _T("%ld:%ld:%ld + %2.1f Hrs"),
                          GmtTime.wHour,
                          GmtTime.wMinute,
                          GmtTime.wSecond,
                          TimeZoneDifference );

问题:如何获取特定时区的TIME_TIMEZONE_INFORMATION？

不幸的是,你不能用win32 API做到这一点.请参阅MSDN,如何在Win32中获取特定的TIME_ZONE_INFORMATION结构？

您将需要创建一个空变量并手动填充它,或使用标准C时间库.