GetCurrentTime(),GetLocalTime(),GetSystemTime()之间的区别

1. GetCurrentTime()

GetCurrentTime()只和16位版本的windows兼容，在32位windows下最好用gettickcount();

2. GetLocalTime()

GetLocalTime()在不同的机器中会有不同的结果，这和你在控制面板中的时区设置有关. 该函数是获取的系统当前所属时区的时间,
比如说, 在北京时区, 那么获取的该时间的时间.

3. GetSystemTime()

GetSystemTime()获取的格林尼治时间, 是全球标准时间.

SYSTEMTIME stUTC;

GetSystemTime(&stUTC);

TCHAR chBuf[nBufSize];

wsprintf(chBuf,_T("UTC: %u/%u/%u %u:%u:%u:%u %d\r\n"),

stUTC.wYear, stUTC.wMonth, stUTC.wDay,

stUTC.wHour, stUTC.wMinute, stUTC.wSecond,

stUTC.wMilliseconds,stUTC.wDayOfWeek);

4. GetTickCount()

GetTickCount()获取的是从设备开机后的毫秒数.
不包括系统的挂起时间.

主要的应用:

dwOldTime = GetTickCount();

DoSomeThing();

dwTimeElapsed = GetTickCount() - dwOldTime;

获取某段程序执行所需的时间.

5. 更好的办法：“now函数”

例如：formatdatetime('yyyy ''年'' m ''月'' d ''日''dddd '+'hh:mm:ssAM/PM',now);

输出结果： 2001年5月8日星期一19：35：40 PM

下附一些时间函数：

The following functions are used with system time.

Function	Description
GetSystemTime	Retrieves the current system date and time in UTC format.
GetSystemTimeAdjustment	Determines whether the system is applying periodic time adjustments to its time-of-day clock.
LocalFileTimeToFileTime	Converts a local file time to a file time based on UTC.
SetSystemTime	Sets the current system time and date.
SetSystemTimeAdjustment	Enables or disables periodic time adjustments to the system's time-of-day clock.
SystemTimeToFileTime	Converts a system time to a file time.
SystemTimeToTzSpecificLocalTime	Converts a UTC time to a specified time zone's corresponding local time.
TzSpecificLocalTimeToSystemTime	Converts a local time to a UTC time.

The following functions are used with local time.

Function	Description
FileTimeToLocalFileTime	Converts a UTC file time to a local file time.
GetLocalTime	Retrieves the current local date and time.
GetTimeZoneInformation	Retrieves the current time-zone parameters.
SetLocalTime	Sets the current local time and date.
SetTimeZoneInformation	Sets the current time-zone parameters.
SystemTimeToTzSpecificLocalTime	Converts a UTC time to a specified time zone's corresponding local time.
TzSpecificLocalTimeToSystemTime	Converts a local time to a UTC time.

The following functions are used with file time.

Function	Description
CompareFileTime	Compares two file times.
FileTimeToLocalFileTime	Converts a UTC file time to a local file time.
FileTimeToSystemTime	Converts a file time to system time format.
GetFileTime	Retrieves the date and time that a file was created, last accessed, and last modified.
GetSystemTimeAsFileTime	Retrieves the current system date and time in UTC format.
LocalFileTimeToFileTime	Converts a local file time to a file time based on UTC.
SetFileTime	Sets the date and time that a file was created, last accessed, or last modified.
SystemTimeToFileTime	Converts a system time to a file time.

The following functions are used with MS-DOS date and time.

Function	Description
DosDateTimeToFileTime	Converts MS-DOS date and time values to a file time.
FileTimeToDosDateTime	Converts a file time to MS-DOS date and time values.

The following functions are used with Windows time.

Function	Description
GetTickCount	Retrieves the number of milliseconds that have elapsed since the system was started.