public int getNumberOfDays()
    {
        int mn = theMonthNumber;
        if (mn == 1 || mn == 3 || mn == 5 || mn == 7 || mn == 8 || mn == 10 || mn == 12)
        {return 31;}
        if (mn == 4 || mn == 6 || mn == 9 || mn == 11)
        {return 30;}
        else
        {return 28;}
    }