WindowsTimeZone

This class is Windows-Only.

Represents a time zone from the Windows registry. Unfortunately, Windows does not use the TZ Database. To use the TZ Database, use PosixTimeZone (which reads its information from the TZ Database files on disk) on Windows by providing the TZ Database files and telling PosixTimeZone.getTimeZone where the directory holding them is.

The TZ Database files and Windows' time zone information frequently do not match. Windows has many errors with regards to when DST switches occur (especially for historical dates). Also, the TZ Database files include far more time zones than Windows does. So, for accurate time zone information, use the TZ Database files with PosixTimeZone rather than WindowsTimeZone. However, because WindowsTimeZone uses Windows system calls to deal with the time, it's far more likely to match the behavior of other Windows programs. Be aware of the differences when selecting a method.

WindowsTimeZone does not exist on Posix systems.

To get a WindowsTimeZone, call WindowsTimeZone.getTimeZone.

version(StdDdoc)

final

class WindowsTimeZone : TimeZone {

bool hasDST [@property getter];

bool dstInEffect(long stdTime);

long utcToTZ(long stdTime);

long tzToUTC(long adjTime);

static immutable(WindowsTimeZone) getTimeZone(string name);

static string[] getInstalledTZNames();

}

Members

Functions

dstInEffect bool dstInEffect(long stdTime): Takes the number of hnsecs (100 ns) since midnight, January 1st, 1 A.D. in UTC time (i.e. std time) and returns whether DST is in effect in this time zone at the given point in time.
tzToUTC long tzToUTC(long adjTime): Takes the number of hnsecs (100 ns) since midnight, January 1st, 1 A.D. in this time zone's time and converts it to UTC (i.e. std time).
utcToTZ long utcToTZ(long stdTime): Takes the number of hnsecs (100 ns) since midnight, January 1st, 1 A.D. in UTC time (i.e. std time) and converts it to this time zone's time.

Properties

hasDST bool hasDST [@property getter]: Whether this time zone has Daylight Savings Time at any point in time. Note that for some time zone types it may not have DST for current dates but will still return true for hasDST because the time zone did at some point have DST.

Static functions

getInstalledTZNames string[] getInstalledTZNames(): Returns a list of the names of the time zones installed on the system. The list returned by WindowsTimeZone contains the Windows TZ names, not the TZ Database names. However, TimeZone.getinstalledTZNames will return the TZ Database names which are equivalent to the Windows TZ names.
getTimeZone immutable(WindowsTimeZone) getTimeZone(string name): Returns a TimeZone with the given name per the Windows time zone names. The time zone information is fetched from the Windows registry.

Inherited Members

From TimeZone

name string name [@property getter]: The name of the time zone. Exactly how the time zone name is formatted depends on the derived class. In the case of PosixTimeZone, it's the TZ Database name, whereas with WindowsTimeZone, it's the name that Windows chose to give the registry key for that time zone (typically the name that they give stdTime if the OS is in English). For other time zone types, what it is depends on how they're implemented.
stdName string stdName [@property getter]: Typically, the abbreviation (generally 3 or 4 letters) for the time zone when DST is not in effect (e.g. PST). It is not necessarily unique.
dstName string dstName [@property getter]: Typically, the abbreviation (generally 3 or 4 letters) for the time zone when DST is in effect (e.g. PDT). It is not necessarily unique.
hasDST bool hasDST [@property getter]: Whether this time zone has Daylight Savings Time at any point in time. Note that for some time zone types it may not have DST for current dates but will still return true for hasDST because the time zone did at some point have DST.
dstInEffect bool dstInEffect(long stdTime): Takes the number of hnsecs (100 ns) since midnight, January 1st, 1 A.D. in UTC time (i.e. std time) and returns whether DST is effect in this time zone at the given point in time.
utcToTZ long utcToTZ(long stdTime): Takes the number of hnsecs (100 ns) since midnight, January 1st, 1 A.D. in UTC time (i.e. std time) and converts it to this time zone's time.
tzToUTC long tzToUTC(long adjTime): Takes the number of hnsecs (100 ns) since midnight, January 1st, 1 A.D. in this time zone's time and converts it to UTC (i.e. std time).
utcOffsetAt Duration utcOffsetAt(long stdTime): Returns what the offset from UTC is at the given std time. It includes the DST offset in effect at that time (if any).