The active read-only property contains details about the active calendar view.
DayPilot.Switcher.activecontrol (DayPilot.Calendar or DayPilot.Month) - the calendar component reference
The returned object has a single member that holds a reference to the active calendar component:
control (DayPilot.Calendar or DayPilot.Month) - the calendar component reference
const activeView = switcher.active;
const calendar = activeView.control;