C#求今天是一年中的第幾周怎麼算?
private int WeekOfYear(string date)
{
DateTime curDay = Convert.ToDateTime(date);
int firstdayofweek = Convert.ToInt32(Convert.ToDateTime(curDay.Year.ToString() + "- " + "1-1 ").DayOfWeek);
int days = curDay.DayOfYear;
int daysOutOneWeek = days - (7 - firstdayofweek);
if (daysOutOneWeek <= 0)
{
return 1;
}
else
{
int weeks = daysOutOneWeek / 7;
if (daysOutOneWeek % 7 != 0)
weeks ++;
return weeks + 1;
}
}
http://blog.csdn.net/letian_fly/article/details/2739618