public string SignRegister(AttendanceDetail detail)
 {
     try
     {
         digitalContext = new DigitalEntities();
         digitalContext.AttendanceDetails.Add(detail);
         digitalContext.SaveChanges();
             return "You signed";                
     }
     catch (Exception )
     {
         return null;
     }
 }
 private void btnSave_Click(object sender, RoutedEventArgs e)
 {
     try
     {
         SignModel signModel = new SignModel();
         if (!Regex.IsMatch(txtHours.Text, "^((?:[0-9]|1[0-9]|2[0-3])(?:\\.\\d{1,2})?|24(?:\\.00?)?)$"))
         {
             MessageBox.Show("Invalid input for Hours");
             txtHours.Clear();
         }
         else
         {
             AttendanceMaster master = new AttendanceMaster();
             master.TrainedOn = txtTask.Text;
             master.AttendanceDate = (DateTime)datePicker.SelectedDate;
             MessageBox.Show(signModel.MasterRecord(master));
             AttendanceDetail detail = new AttendanceDetail();
             decimal hrs = decimal.Parse(txtHours.Text, CultureInfo.InvariantCulture);
             detail.HoursPerDay = hrs;                 
             detail.MasterID = master.MasterID;
             MessageBox.Show(signModel.SignRegister(detail));
             txtHours.Clear();
             txtTask.Clear();
             LoadData();
         }
     }
     catch (Exception ex)
     {
         MessageBox.Show(ex.Message);
     }
 }