daylight_delta()

xtd::time_span xtd::time_zone_info::adjustement_rule::daylight_delta ( ) const

noexcept

Gets the amount of time that is required to form the time zone's daylight saving time. This amount of time is added to the time zone's offset from Coordinated Universal Time (UTC).

Returns

A xtd::time_span object that indicates the amount of time to add to the standard time changes as a result of the adjustment rule.

Remarks

The following formula defines a time zone's daylight saving time:

time_tone_time = base_utc_offset + daylight_delta + utc_time

The value of the xtd::time_zone_info::adjustement_rule::daylight_delta property can range from 14 hours to -14 hours.

Note

The xtd::time_zone_info::adjustement_rule::daylight_delta property measures the difference between the time zone's standard time and its daylight saving time. It does not apply to changes in a time zone's standard offset from Coordinated Universal Time (UTC). To represent a time zone that has changed its standard time offset from UTC, you must call the CreateCustomTimeZone method to create a new time zone.

Remarks

The most common value of the xtd::time_zone_info::adjustement_rule::daylight_delta property is 1.0 hours. The application of the daylight saving time adjustment rule increases the time zone's offset from Coordinated Universal Time (UTC) by one hour.