Windows.Globalization.Calendar.AddHours C# (CSharp) Method

		public extern void AddHours([In] int hours);
		public extern string HourAsString();

        /// <summary>
        /// Sets zero based calendar hour.
        /// </summary>
        internal static void SetZeroBasedHour(this Windows.Globalization.Calendar calendar, int hour)
        {
            if (calendar.GetClock() == ClockIdentifiers.TwentyFourHour)
            {
                if (hour < 0 || hour > 23)
                {
                    throw new ArgumentException("Hour should be between 0 and 23.");
                }

                calendar.AddHours(hour - calendar.Hour);
            }
            else
            {
                if (hour < 0 || hour > 11)
                {
                    throw new ArgumentException("Hour should be between 0 and 11.");
                }
                var calendarHour = calendar.Hour == 12 ? 0 : calendar.Hour;
                calendar.AddHours(hour - calendarHour);
            }
        }