DateTime date = new DateTime(2006, 1, 1);
DateTime m = date.AddDays((n-1) * 7);
int w = (int)(DayOfWeek.Monday - m.DayOfWeek);
if(w==1)
{
w = -6;
}
DataTable resultDate = m.AddDays(w);
DateTime date = new DateTime(2006, 1, 1);//2006年1月1日,假设星期X
DateTime m = date.AddDays((n-1) * 7);//第n周的星期X
int w = DayOfWeek.Monday - m.DayOfWeek;//星期一与星期X的差,负数
DataTable resultDate = m.AddDays(w);//第n周的星期X倒推回第n周星期一
DateTime date = new DateTime(2006, 1, 1);
DateTime m = date.AddDays((n-1) * 7);
int w = DayOfWeek.Monday - m.DayOfWeek;
DataTable resultDate = m.AddDays(w);
DateTime date = new DateTime(2006, 1, 1);
DateTime m = date.AddDays(10 * 7);
int w = m.DayOfWeek - DayOfWeek.Sunday;
DateTime resultDate = m.AddDays(w);
DateTime date = new DateTime(2006, 1, 1);
DateTime m = date.AddDays(10 * 7);
int w = m.DayOfWeek - DayOfWeek.Monday;
DataTable resultDate = m.AddDays(w);