public static DateTime CreateNextDayByWeek(DateTime dt, DayOfWeek dayOfWeek) => DateTimeCalc.OffsetByWeekAfter(dt, dayOfWeek);
public static DateTime CreateNextDayByWeek(int year, int month, int day, DayOfWeek dayOfWeek) => DateTimeCalc.OffsetByWeekAfter(Create(year, month, day), dayOfWeek);