获取下一天日期

    //获取当月有多少天， bLeapYear判断是否闰年    int getDaysInMonth(int month, bool bLeapYear)    {        switch(month)        {        case 1:        case 3:        case 5:        case 7:        case 8:        case 10:        case 12:            return 31;        case 2:            if (bLeapYear)            {                return 29;            }            else                return 28;        case 4:        case 6:        case 9:        case 11:            return 30;        }        return -1;    }    //获取st的下一天    SYSTEMTIME getNextDay(SYSTEMTIME st)    {        //判断闰年        bool bLeapYear = false;        if ( (st.wYear % 4 == 0 && st.wYear % 100 != 0) || st.wYear % 400 == 0 )        {            bLeapYear = true;        }        int tomorrowYear = st.wYear;        int tomorrowMonth = st.wMonth;        int tomorrowDay = st.wDay + 1;        int tomorrowWeek = st.wDayOfWeek + 1;        int days = getDaysInMonth(tomorrowMonth, bLeapYear);        //next month        if(tomorrowDay > days)        {            tomorrowDay = 1;            tomorrowMonth += 1;            //next year            if(tomorrowMonth > 12)            {                tomorrowMonth = 1;                tomorrowYear += 1;            }        }        //week        if (tomorrowWeek > 7)        {            tomorrowWeek = 1;        }        SYSTEMTIME tomorrowTime = st;        tomorrowTime.wYear = tomorrowYear;        tomorrowTime.wMonth = tomorrowMonth;        tomorrowTime.wDay = tomorrowDay;        tomorrowTime.wDayOfWeek = tomorrowWeek;        return tomorrowTime;    }