public static bool UpdateAppointment(string connectionString, Appointment appointment)
 {
     try
     {
         using (var context = new AppointmentDBContext(connectionString))
         {
             context.Appointments.Add(appointment);
             var entry = context.Entry(appointment);
             entry.State = EntityState.Modified;
             var result = context.SaveChanges();
             return(result > 0);
         }
     }
     catch (Exception exception)
     {
         NLogLogger.LogError(exception, TitleResources.Error, ExceptionResources.ExceptionOccured,
                             ExceptionResources.ExceptionOccuredLogDetail);
         return(false);
     }
 }
        public static bool UpdateAppointments(string connectionString, IEnumerable<Appointment> appointments)
        {
            try
            {
                using (var context = new AppointmentDBContext(connectionString))
                {
                    foreach (var appointment in appointments)
                    {
                        context.Appointments.Add(appointment);
                        var entry = context.Entry(appointment);
                        entry.State = EntityState.Modified;
                    }

                    var result = context.SaveChanges();
                    return result > 0;
                }
            }
            catch (Exception exception)
            {
                NLogLogger.LogError(exception, TitleResources.Error, ExceptionResources.ExceptionOccured,
                                    ExceptionResources.ExceptionOccuredLogDetail);
                return false;
            }
        }