public CalEvent CalendarEventTest() { // Testing Calendar Event CalEvent e = new CalEvent(); e.SetLocation("Brussels"); e.SetTitle("Meeting with Zosha"); e.SetRecurring(true); e.SetStartDate(new DateTime(2019, 12, 12)); e.SetEndDate(new DateTime(2020, 01, 01)); e.InitNullValues(); // String[] arr ={ "Tuesday", "Monday", "Sunday" }; e.SetRecurringType("Friday"); var dates = e.GetDates(); StringBuilder str = new StringBuilder(); foreach (var item in dates) { Console.WriteLine(item.ToString()); str.Append(item + "\n"); } MessageBox.Show(str.ToString()); return(e); }