DateTime dtTime1 = dateTimePicker1.Value.Date;
            DateTime dtTime2 = dateTimePicker2.Value.Date;
            int iTotalDays = 0;
            if (dtTime1.Year == dtTime2.Year)
            {
                int iFirstMonth = dtTime1.DayOfYear;
                int iLastMonth = dtTime2.DayOfYear;                

                if (iFirstMonth > iLastMonth)
                {
                    iTotalDays = iFirstMonth - iLastMonth;
                }
                else
                {
                    iTotalDays = iLastMonth - iFirstMonth;
                }
            }