I've list of tasks, every task will have properties of start date, end date, start time and end time. is there a way to show these tasks in xammonthcalendar?
The xamMonthCalendar is analogous to the WinForms MonthCalendar and is a means of displaying 1 or more months. If you just want to make certain days appear differently depending on the date they represent then you could use the CalendarDayStyleSelector. There is a sample in the feature browser which demonstrates using this to make certain days appear differently.