The DatePeriod class

(PHP 5 >= 5.3.0, PHP 7)

简介

Represents a date period.

A date period allows iteration over a set of dates and times, recurring at regular intervals, over a given period.

类摘要

DatePeriod implements Traversable {
/* 常量 */
const integer EXCLUDE_START_DATE = 1 ;
/* 方法 */
public __construct ( DateTimeInterface $start , DateInterval $interval , int $recurrences [, int $options ] )
public __construct ( DateTimeInterface $start , DateInterval $interval , DateTimeInterface $end [, int $options ] )
public __construct ( string $isostr [, int $options ] )
public DateInterval getDateInterval ( void )
public DateTimeInterface getEndDate ( void )
public DateTimeInterface getStartDate ( void )
}

预定义常量

DatePeriod::EXCLUDE_START_DATE

Exclude start date, used in DatePeriod::__construct().

Table of Contents

User Contributed Notes

mike at saymikeo dot com 12-May-2017 01:06
Calculating business days can be cumbersome. Here is an iterator for handling business days. Usage examples below for adding # of business days and calculating how many business days between two dates.

Here is the iterator class
https://gist.github.com/styks1987/29dd0f6a68e3b07ba70fec18f732eb86

Usage

Counting # of Business Days between two dates

<?php
function countBusinessDays($start, $stop)
    {
        if($start > $stop){
            $tmpStart = clone $start;
            $start = clone $stop;
            $stop = clone $tmpStart;
        }

        // Adding the time to the end date will include it
        $period = new \DatePeriod($start->setTime(0,0,0), new \DateInterval('P1D'), $stop->setTime(23,59,59), \DatePeriod::EXCLUDE_START_DATE);
        $periodIterator = new BusinessDayPeriodIterator($period);
        $businessDays = 0;
        while($periodIterator->valid()){
            // If we run into a weekend, don't count it
            if(!$periodIterator->isWeekend()){
                $businessDays++;
            }
            $periodIterator->next();
        }

        return $businessDays;
    }
?>

Add # of business days

<?php
function addBusinessDays(\DateTime $startDateTime, $daysToAdd)
    {
        $endDateTime = clone $startDateTime;
        $endDateTime->add(new \DateInterval('P' . $daysToAdd . 'D'))->setTime(23,59,59);
        $period = new \DatePeriod($startDateTime, new \DateInterval('P1D'), $endDateTime);

        $periodIterator = new BusinessDayPeriodIterator($period);
        $adjustedEndingDate = clone $startDateTime;
        while($periodIterator->valid()){
            $adjustedEndingDate = $periodIterator->current();
            // If we run into a weekend, extend our days
            if($periodIterator->isWeekend()){
                $periodIterator->extend();
            }
            $periodIterator->next();
        }

        return $adjustedEndingDate;
    }
?>
mail at pascalhofmann dot de 19-Jan-2017 06:58
When looping over a DatePeriod object, the returned objects always implement DateTimeInterface. The exact type returned depends on how the DatePeriod was created. If $start was a DateTimeImmutable, the objects returned will be of type DateTimeImmutable. If a DateTime object was used, the objects returned will be of type DateTime.
php at karlsruler dot de 22-Jun-2015 09:34
The iterator seems to check the time as well, it excludes the end element if its time is 00:00:00. So the slightly safer version (to compare it against joshs suggestion) is to use $date->setTime(23, 59, 59) instead of $date->modify("+1 day").
patrick at adrichem dot nu 22-Jan-2014 08:32
DatePeriod is not compatible with negative intervals.

To do so you can simply use DateInterval and loop through it yourself like this: (not start should be ahead of end if you use a negative interval

    class DateRange extends ArrayIterator
    {

        protected $oDate = null;
        protected $oStartDate = null;
        protected $oEndDate = null;
        protected $oInterval = null;

        public function __construct( DateTime $oStartDate, DateTime $oEndDate, DateInterval $oInterval = null )
        {
            $this->oStartDate = $oStartDate;
            $this->oDate = clone $oStartDate;
            $this->oEndDate = $oEndDate;
            $this->oInterval = $oInterval;
        }

        public function next()
        {
            $this->oDate->add($this->oInterval);
            return $this->oDate;
        }

        public function current()
        {
            return $this->oDate;
        }

        public function valid()
        {
            if ($this->oStartDate > $this->oEndDate)
            {
                return $this->oDate >= $this->oEndDate;
            }
            return $this->oDate <= $this->oEndDate;
        }

    }

$oRange = new DateRange(new DateTime("2013-10-01"), new DateTime("2013-01-01"), DateInterval::createFromDateString("-1 month") );
    foreach ($oRange as $oDate)
    {
        echo $oDate->format("Y-m-d") . "<br />";
    }
josh dot love at verizon dot net 27-Aug-2012 11:23
Just an example to include the end date using the DateTime method 'modify'

<?php

$begin = new DateTime( '2012-08-01' );
$end = new DateTime( '2012-08-31' );
$end = $end->modify( '+1 day' );

$interval = new DateInterval('P1D');
$daterange = new DatePeriod($begin, $interval ,$end);

foreach($daterange as $date){
    echo $date->format("Ymd") . "<br>";
}
?>
logos-php at kith dot org 06-Jul-2012 04:18
Thanks much to those of you who supplied sample code; that helps a lot.

I wanted to mention another thing that helped me: when you do that foreach ( $period as $dt ), the $dt values are DateTime objects.

That may be obvious to those of you with more experience, but I wasn't sure until I looked it up on Stack Overflow. So I figured it was worth posting here to help others like me who might've been confused or uncertain.
Aurelien Marchand 09-Mar-2011 09:11
Warning About DatePeriod for Some Versions of PHP
*****************************************

Some versions of PHP had a bug so that caused DatePeriod to act strangely. For instance, the following code:

<?php
$start = DateTime::createFromFormat("Y-m-d H:i:s","2011-01-01 00:00:00",new DateTimeZone("America/Toronto"));
$interval = new DateInterval("P1M"); // 1 month
$occurrences = 3;
$period = new DatePeriod($start,$interval,$occurrences);
foreach($period as $dt){
  echo $dt->format("Y-m-d H:i:s") . "\n";
}
foreach($period as $dt){
  echo $dt->format("Y-m-d H:i:s") . "\n";
}
?>

Would produce the following text:
2011-01-01 00:00:00
2011-02-01 00:00:00
2011-03-01 00:00:00
2011-04-01 00:00:00
2011-05-01 00:00:00
2011-06-01 00:00:00
2011-07-01 00:00:00
2011-08-01 00:00:00

Instead of:
2011-01-01 00:00:00
2011-02-01 00:00:00
2011-03-01 00:00:00
2011-04-01 00:00:00
2011-01-01 00:00:00
2011-02-01 00:00:00
2011-03-01 00:00:00
2011-04-01 00:00:00

5.3.2 fails
5.3.3 fails
5.3.4 -??-
5.3.5 works
Memori 25-Feb-2011 09:19
If you want to include the end-date, add one day to it:

<?php
$startDate = new DateTime();
$endDate = new DateTime();

$startDateInt = new DateInterval( "P1Y" );
$endDateInt = new DateInterval( "P1D" );

$startDate->sub( $startDateInt );
$endDate->add( $endDateInt );

$periodInt = new DateInterval( "P1M" );
$period = new DatePeriod( $startDate, $periodInt, $endDate );

// At februari 2011:
// $period = (8,9,10,11,12,1,2)
?>
jkaatz at gmx dot de 10-Jul-2009 10:55
Nice example from PHP Spring Conference (thanks to Johannes Schlüter and David Zülke)

<?php
$begin = new DateTime( '2007-12-31' );
$end = new DateTime( '2009-12-31 23:59:59' );

$interval = DateInterval::createFromDateString('last thursday of next month');
$period = new DatePeriod($begin, $interval, $end, DatePeriod::EXCLUDE_START_DATE);

foreach ( $period as $dt )
  echo $dt->format( "l Y-m-d H:i:s\n" );
?>

DateInterval specs could be found at http://en.wikipedia.org/wiki/ISO_8601#Time_intervals