calc.class.php

一个用PHP编写的

//        }
//        $first_week_days %= 7;
//        return (ceil((Date_Calc::daysInMonth($month, $year) - $first_week_days) / 7) + $weeks);
//    } // end func weeksInMonth
//
//    /**
//     * Find the day of the week for the first of the month of given date.
//     *
//     * @param string month in format MM, default is current local month
//     * @param string year in format CCYY, default is current local year
//     *
//     * @access public
//     *
//     * @return int number of weekday for the first day, 0=Sunday
//     */
//
//    function firstOfMonthWeekday($month='',$year='')
//    {
//        if (empty($year)) {
//            $year = Date_Calc::dateNow('%Y');
//        }
//        if (empty($month)) {
//            $month = Date_Calc::dateNow('%m');
//        }
//
//        return(Date_Calc::dayOfWeek('01',$month,$year));
//    } // end func firstOfMonthWeekday
//
//    /**
//     * Return date of first day of month of given date.
//     *
//     * @param string month in format MM, default is current local month
//     * @param string year in format CCYY, default is current local year
//     * @param string format for returned date
//     *
//     * @access public
//     *
//     * @return string date in given format
//     */
//
//    function beginOfMonth($month='',$year='',$format='%Y%m%d')
//    {
//        if (empty($year)) {
//            $year = Date_Calc::dateNow('%Y');
//        }
//        if (empty($month)) {
//            $month = Date_Calc::dateNow('%m');
//        }
//
//        return(Date_Calc::dateFormat('01',$month,$year,$format));
//    } // end of func beginOfMonth
//
//    /**
//     * Find the month day of the beginning of week for given date,
//     * using DATE_CALC_BEGIN_WEEKDAY. (can return weekday of prev month.)
//     *
//     * @param string day in format DD, default is current local day
//     * @param string month in format MM, default is current local month
//     * @param string year in format CCYY, default is current local year
//     * @param string format for returned date
//     *
//     * @access public
//     *
//     * @return string date in given format
//     */
//
//    function beginOfWeek($day='',$month='',$year='',$format='%Y%m%d')
//    {
//        if (empty($year)) {
//            $year = Date_Calc::dateNow('%Y');
//        }
//        if (empty($month)) {
//            $month = Date_Calc::dateNow('%m');
//        }
//        if (empty($day)) {
//            $day = Date_Calc::dateNow('%d');
//        }
//
//        $this_weekday = Date_Calc::dayOfWeek($day,$month,$year);
//
//        $interval = (7 - DATE_CALC_BEGIN_WEEKDAY + $this_weekday) % 7;
//
//        return(Date_Calc::daysToDate(Date_Calc::dateToDays($day,$month,$year) - $interval,$format));
//    } // end of func beginOfWeek
//
//    /**
//     * Find the month day of the end of week for given date,
//     * using DATE_CALC_BEGIN_WEEKDAY. (can return weekday
//     * of following month.)
//     *
//     * @param string day in format DD, default is current local day
//     * @param string month in format MM, default is current local month
//     * @param string year in format CCYY, default is current local year
//     * @param string format for returned date
//     *
//     * @access public
//     *
//     * @return string date in given format
//     */
//
//    function endOfWeek($day='',$month='',$year='',$format='%Y%m%d')
//    {
//        if (empty($year)) {
//            $year = Date_Calc::dateNow('%Y');
//        }
//        if (empty($month)) {
//            $month = Date_Calc::dateNow('%m');
//        }
//        if (empty($day)) {
//            $day = Date_Calc::dateNow('%d');
//        }
//
//
//        $this_weekday = Date_Calc::dayOfWeek($day,$month,$year);
//
//        $interval = (6 + DATE_CALC_BEGIN_WEEKDAY - $this_weekday) % 7;
//
//        return(Date_Calc::daysToDate(Date_Calc::dateToDays($day,$month,$year) + $interval,$format));
//    } // end func endOfWeek
//
//    /**
//     * Find the month day of the beginning of week after given date,
//     * using DATE_CALC_BEGIN_WEEKDAY. (can return weekday of prev month.)
//     *
//     * @param string day in format DD, default is current local day
//     * @param string month in format MM, default is current local month
//     * @param string year in format CCYY, default is current local year
//     * @param string format for returned date
//     *
//     * @access public
//     *
//     * @return string date in given format
//     */
//
//    function beginOfNextWeek($day='',$month='',$year='',$format='%Y%m%d')
//    {
//        if (empty($year)) {
//            $year = Date_Calc::dateNow("%Y");
//        }
//        if (empty($month)) {
//            $month = Date_Calc::dateNow("%m");
//        }
//        if (empty($day)) {
//            $day = Date_Calc::dateNow("%d");
//        }
//
//        $date = Date_Calc::daysToDate(
//                    Date_Calc::dateToDays($day+7,$month,$year),"%Y%m%d"
//                );
//
//        $next_week_year = substr($date,0,4);
//        $next_week_month = substr($date,4,2);
//        $next_week_day = substr($date,6,2);
//
//        return Date_Calc::beginOfWeek(
//                            $next_week_day,$next_week_month,$next_week_year,
//                            $format
//                        );
//
//        $date = Date_Calc::daysToDate(Date_Calc::dateToDays($day+7,$month,$year),"%Y%m%d");
//    } // end func beginOfNextWeek
//
//    /**
//     * Find the month day of the beginning of week before given date,
//     * using DATE_CALC_BEGIN_WEEKDAY. (can return weekday of prev month.)
//     *
//     * @param string day in format DD, default is current local day
//     * @param string month in format MM, default is current local month
//     * @param string year in format CCYY, default is current local year
//     * @param string format for returned date
//     *
//     * @access public
//     *
//     * @return string date in given format
//     */
//
//    function beginOfPrevWeek($day='',$month='',$year='',$format='%Y%m%d')
//    {
//        if (empty($year)) {
//            $year = Date_Calc::dateNow("%Y");
//        }
//        if (empty($month)) {
//            $month = Date_Calc::dateNow("%m");
//        }
//        if (empty($day)) {
//            $day = Date_Calc::dateNow("%d");
//        }
//
//        $date = Date_Calc::daysToDate(
//                        Date_Calc::dateToDays($day-7,$month,$year),"%Y%m%d"
//                    );
//
//        $prev_week_year = substr($date,0,4);
//        $prev_week_month = substr($date,4,2);
//        $prev_week_day = substr($date,6,2);
//
//        return Date_Calc::beginOfWeek($prev_week_day,$prev_week_month,$prev_week_year,$format);
//
//
//        $date = Date_Calc::daysToDate(Date_Calc::dateToDays($day-7,$month,$year),"%Y%m%d");
//    } // end func beginOfPrevWeek
//
//    /**
//     * Return an array with days in week
//     *
//     * @param string day in format DD, default is current local day
//     * @param string month in format MM, default is current local month
//     * @param string year in format CCYY, default is current local year
//     * @param string format for returned date
//     *
//     * @access public
//     *
//     * @return array $week[$weekday]
//     */
//
//    function getCalendarWeek($day='',$month='',$year='',$format='%Y%m%d')
//    {
//        if (empty($year)) {
//            $year = Date_Calc::dateNow('%Y');
//        }
//        if (empty($month)) {
//            $month = Date_Calc::dateNow('%m');
//        }
//        if (empty($day)) {
//            $day = Date_Calc::dateNow('%d');
//        }
//
//        $week_array = array();
//
//        // date for the column of week
//
//        $curr_day = Date_Calc::beginOfWeek($day,$month,$year,'%E');
//
//        for($counter=0; $counter <= 6; $counter++) {
//            $week_array[$counter] = Date_Calc::daysToDate($curr_day,$format);
//            $curr_day++;
//        }
//
//        return $week_array;
//    } // end func getCalendarWeek
//
//    /**
//     * Return a set of arrays to construct a calendar month for
//     * the given date.
//     *
//     * @param string month in format MM, default is current local month
//     * @param string year in format CCYY, default is current local year
//     * @param string format for returned date
//     *
//     * @access public
//     *
//     * @return array $month[$row][$col]
//     */
//
//    function getCalendarMonth($month='',$year='',$format='%Y%m%d')
//    {
//        if (empty($year)) {
//            $year = Date_Calc::dateNow('%Y');
//        }
//        if (empty($month)) {
//            $month = Date_Calc::dateNow('%m');
//        }
//
//        $month_array = array();
//
//        // date for the first row, first column of calendar month
//        if (DATE_CALC_BEGIN_WEEKDAY == 1) {
//            if (Date_Calc::firstOfMonthWeekday($month,$year) == 0) {
//                $curr_day = Date_Calc::dateToDays('01',$month,$year) - 6;
//            } else {
//                $curr_day = Date_Calc::dateToDays('01',$month,$year)
//                    - Date_Calc::firstOfMonthWeekday($month,$year) + 1;
//            }
//        } else {
//            $curr_day = (Date_Calc::dateToDays('01',$month,$year)
//                - Date_Calc::firstOfMonthWeekday($month,$year));
//        }
//
//        // number of days in this month
//        $daysInMonth = Date_Calc::daysInMonth($month,$year);
//
//        $weeksInMonth = Date_Calc::weeksInMonth($month,$year);
//        for($row_counter=0; $row_counter < $weeksInMonth; $row_counter++) {
//            for($column_counter=0; $column_counter <= 6; $column_counter++) {
//                $month_array[$row_counter][$column_counter] =
//                    Date_Calc::daysToDate($curr_day,$format);
//                $curr_day++;
//            }
//        }
//
//        return $month_array;
//    } // end func getCalendarMonth
//
//    /**
//     * Return a set of arrays to construct a calendar year for
//     * the given date.
//     *
//     * @param string year in format CCYY, default current local year
//     * @param string format for returned date
//     *
//     * @access public
//     *
//     * @return array $year[$month][$row][$col]
//     */
//
//    function getCalendarYear($year='',$format='%Y%m%d')
//    {
//        if (empty($year)) {
//            $year = Date_Calc::dateNow('%Y');
//        }
//
//        $year_array = array();
//
//        for($curr_month=0; $curr_month <=11; $curr_month++) {
//            $year_array[$curr_month] =
//                Date_Calc::getCalendarMonth(sprintf('%02d',$curr_month+1),$year,$format);
//        }
//
//        return $year_array;
//    } // end func getCalendarYear
//
    /**
     * Converts a date to number of days since a
     * distant unspecified epoch.
     *
     * @param string day in format DD
     * @param string month in format MM
     * @param string year in format CCYY
     *
     * @access public
     *
     * @return integer number of days
     */

    function dateToDays($day,$month,$year)
    {

        $century = (int) substr($year,0,2);
        $year = (int) substr($year,2,2);

        if ($month > 2) {
            $month -= 3;
        } else {
            $month += 9;
            if ($year) {
                $year--;
            } else {
                $year = 99;
                $century --;
            }
        }

        return (floor(( 146097 * $century) / 4 ) +
            floor(( 1461 * $year) / 4 ) +
            floor(( 153 * $month + 2) / 5 ) +
            $day + 1721119);
    } 

    /**
     * Converts number of days to a distant unspecified epoch.
     *
     * @param int number of days
     * @param string format for returned date
     *
     * @access public
     *
     * @return string date in specified format
     */

    function daysToDate($days,$format='%Y%m%d')
    {

        $days       -=  1721119;
        $century    =   floor(( 4 * $days - 1) / 146097);
        $days       =   floor(4 * $days - 1 - 146097 * $century);
        $day        =   floor($days / 4);

        $year       =   floor(( 4 * $day +  3) / 1461);
        $day        =   floor(4 * $day +  3 - 1461 * $year);
        $day        =   floor(($day +  4) / 4);

        $month      =   floor(( 5 * $day - 3) / 153);
        $day        =   floor(5 * $day - 3 - 153 * $month);
        $day        =   floor(($day +  5) /  5);

        if ($month < 10) {
            $month +=3;
        } else {
            $month -=9;
            if ($year++ == 99) {
                $year = 0;
                $century++;
            }
        }

        $century = sprintf('%02d',$century);
        $year = sprintf('%02d',$year);
        return(Date_Calc::dateFormat($day,$month,$century.$year,$format));
    }

//    /**
//     * Calculates the date of the Nth weekday of the month,
//     * such as the second Saturday of January 2000.
//     *
//     * @param string occurance: 1=first, 2=second, 3=third, etc.
//     * @param string dayOfWeek: 0=Sunday, 1=Monday, etc.
//     * @param string month in format MM
//     * @param string year in format CCYY
//     * @param string format for returned date
//     *
//     * @access public
//     *
//     * @return string date in given format
//     */
//
//    function NWeekdayOfMonth($occurance,$dayOfWeek,$month,$year,$format='%Y%m%d')
//    {
//        $year = sprintf('%04d',$year);
//        $month = sprintf('%02d',$month);
//
//        $DOW1day = sprintf('%02d',(($occurance - 1) * 7 + 1));
//        $DOW1 = Date_Calc::dayOfWeek($DOW1day,$month,$year);
//
//        $wdate = ($occurance - 1) * 7 + 1 +
//                (7 + $dayOfWeek - $DOW1) % 7;
//
//        if ( $wdate > Date_Calc::daysInMonth($month,$year)) {
//            return -1;
//        } else {
//            return(Date_Calc::dateFormat($wdate,$month,$year,$format));
//        }
//    } // end func NWeekdayOfMonth
//
    /**
     *  Formats the date in the given format, much like