Code:
/// <summary>
/// 计算某年第一周的天数
/// </summary>
/// <param name="dt">某年中的一个时间</param>
/// <returns></returns>
public static int DaysInFirstweekInYear(DateTime dt)
{
DateTime FirstDate = Convert.ToDateTime(string.Format("{0}-1-1", dt.Year));
int DayOfWeekInYear = DayOfWeek(FirstDate);
int DaysInFirstWeek = 8 - DayOfWeekInYear;
return DaysInFirstWeek;
}
/// <summary>
/// 一年中的第几周
/// </summary>
/// <param name="dt"></param>
/// <returns></returns>
public static int WeekOfYear(DateTime dt)