int year = DateTime.Now.Year;
int month = DateTime.Now.Month;
DateTime firstDayOfThisMonth = new DateTime(year, month, 1);
DateTime lastDayOfThisMonth = new DateTime(year, month, DateTime.DaysInMonth(year, month));
int month = DateTime.Now.Month;
DateTime firstDayOfThisMonth = new DateTime(year, month, 1);
DateTime lastDayOfThisMonth = new DateTime(year, month, DateTime.DaysInMonth(year, month));