Example requires a windows form and a MonthCalendar control named monthCalendar1.
You can find the start and end dates from the SelectionRange property, see this:
[vb]
Dim selectedDateRange As SelectionRange = MonthCalendar1.SelectionRange Dim StartDate As Date Dim EndDate As Date StartDate = selectedDateRange.Start EndDate = selectedDateRange.End
[c#]
SelectionRange selectedDateRange = MonthCalendar1.SelectionRange; System.DateTime StartDate = selectedDateRange.Start; System.DateTime EndDate = selectedDateRange.End;