private void TimeCardSubmit_Button_Click(object sender, EventArgs e)
        {
            TwentyFourHourTime startTime;
            TwentyFourHourTime endTime;
            TwentyFourHourTime bedTime;
            BabysitterTimeCard timeCard;
            BabysitterPaySheet paySheet;

            startTime = InitializeTime((TIME_OF_DAY)StartTime_AMPM_ComboBox.SelectedItem, StartTimeHour_NumericUpDown.Value, StartTimeMinute_NumericUpDown.Value);
            endTime   = InitializeTime((TIME_OF_DAY)EndTime_AMPM_ComboBox.SelectedItem, EndTimeHour_NumericUpDown.Value, EndTimeMinute_NumericUpDown.Value);

            bedTime = InitializeTime((TIME_OF_DAY)BedTime_AMPM_ComboBox.SelectedItem, BedTimeHour_NumericUpDown.Value, BedTimeMinute_NumericUpDown.Value);
            try
            {
                timeCard = new BabysitterTimeCard(startTime, endTime, bedTime);

                if (timeCard.CalculateHoursAfterMidnight() != 0)
                {
                    paySheet = new BabysitterPaySheet(timeCard.CalculateHoursBeforeBedtime(), timeCard.CalculateHoursBetweenBedtimeAndMidnight(), timeCard.CalculateHoursAfterMidnight());
                }
                else
                {
                    paySheet = new BabysitterPaySheet(timeCard.CalculateHoursBeforeBedtime(), timeCard.CalculateHoursBetweenBedtimeAndMidnight());
                }

                UpdatePaysheet(timeCard, paySheet);
            }
            catch (ArgumentException ex)
            {
                MessageBox.Show(ex.Message.ToString(), "Time Sheet Error");
            }
        }
        private void UpdatePaysheet(BabysitterTimeCard timeCard, BabysitterPaySheet paySheet)
        {
            HoursBeforeBedtime_TextBox.Text     = timeCard.CalculateHoursBeforeBedtime().ToString();
            HoursBedTimeToMidnight_TextBox.Text = timeCard.CalculateHoursBetweenBedtimeAndMidnight().ToString();
            HoursAfterMidnight_TextBox.Text     = timeCard.CalculateHoursAfterMidnight().ToString();

            Pay_TextBox.Text = paySheet.Pay.ToString();
        }