By default, the FirstDayOfWeek property is set to Default. When left set to this, the DayOfWeekEnum considered the first day of the week is based on the system settings of the system using the component.
The WeekRule and FirstDayOfWeekResolved are used to calculate the date which starts the first week of the year. As such, a Week object is not fixed to a particular range of dates but is instead associated with a range of dates based on the calculated first week of the year. For more information on how the date of the first week of the year is calculated, refer to the GetFirstWeekOfYearDate method.
Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2