In the Calendar "FullCalendar" made by http://arshaw.com/fullcalendar/
I need the user can only select one timeslots by clicking in agendaWeek view mode!
The more info you can provide, the more relevant answers we can provide. From what I understand, you can do this by combining dayclick with the select method. http://arshaw.com/fullcalendar/docs/selection/select_method/
Use dayclick to listen for a times lot selection and then use the select method to select the times slot given. I haven't tested this myself but in theory it should work.