At the start of daylight - saving time , the clock time is advanced by the length of time specified in this property 夏时制开始时,时钟时间按此属性中指定的时间长度向前调整。
At the end of daylight - saving time , the clock time is set back by the length of time specified in this property 夏时制结束时,时钟时间会按此属性中指定的时间长度向后调整。
If this value is negative , the clock time is set back at the start of daylight - saving time and advanced at the end 如果此值为负值,则时钟时间会在夏时制开始时向后调整,而在夏时制结束时向前调整。