public void GetAppointmentList()
        {
            List <Appointment> appointmentsId = appointmentManager.GetAppointmentList();

            foreach (var item in appointmentsId)
            {
                AppointmentsId.Add(item);
            }

            if (appointmentsId.Count < 1)
            {
                MessageBox.Show("No Apoointments Found !");
            }
        }