DatePeriod::__construct
(PHP 5 >= 5.3.0)
DatePeriod::__construct — Creates a new DatePeriod object
Description
public DatePeriod::__construct
( DateTime
$start
, DateInterval $interval
, int $recurrences
[, int $options
] )
public DatePeriod::__construct
( DateTime
$start
, DateInterval $interval
, DateTime $end
[, int $options
] )
public DatePeriod::__construct
( string
$isostr
[, int $options
] )Creates a new DatePeriod object.
Parameters
-
start -
The start date of the period.
-
interval -
The interval between recurrences within the period.
-
recurrences -
The number of recurrences.
-
end -
The end date of the period.
-
isostr -
An ISO 8601 repeating interval specification.
-
options -
Can be set to
DatePeriod::EXCLUDE_START_DATEto exclude the start date from the set of recurring dates within the period.
Examples
Example #1 DatePeriod example
<?php
$start = new DateTime('2012-07-01');
$interval = new DateInterval('P7D');
$end = new DateTime('2012-07-31');
$recurrences = 4;
$iso = 'R4/2012-07-01T00:00:00Z/P7D';
// All of these periods are equivalent.
$period = new DatePeriod($start, $interval, $recurrences);
$period = new DatePeriod($start, $interval, $end);
$period = new DatePeriod($iso);
// By iterating over the DatePeriod object, all of the
// recurring dates within that period are printed.
foreach ($period as $date) {
echo $date->format('Y-m-d')."\n";
}
?>
The above example will output:
2012-07-01 2012-07-08 2012-07-15 2012-07-22 2012-07-29
Example #2 DatePeriod example with DatePeriod::EXCLUDE_START_DATE
<?php
$start = new DateTime('2012-07-01');
$interval = new DateInterval('P7D');
$end = new DateTime('2012-07-31');
$period = new DatePeriod($start, $interval, $end,
DatePeriod::EXCLUDE_START_DATE);
// By iterating over the DatePeriod object, all of the
// recurring dates within that period are printed.
// Note that, in this case, 2012-07-01 is not printed.
foreach ($period as $date) {
echo $date->format('Y-m-d')."\n";
}
?>
The above example will output:
2012-07-08 2012-07-15 2012-07-22 2012-07-29
Коментарии
I found two things useful to know that aren't covered here.
1. endDate is excluded:
<?php
$i = new DateInterval('P1D');
$d1 = new Datetime();
$d2 = clone $d1; $d2->add($i);
foreach(new DatePeriod($d1, $i, $d2) as $d) {
echo $d->format('Y-m-d H:i:s') . "\n";
}
?>
Will output:
2010-11-03 12:39:53
(Another one because I got it wrong at first)
2. For the first form, recurrences really means REcurrences, not occurences.
<?php
$i = new DateInterval('P1D');
$d = new Datetime();
foreach(new DatePeriod($d, $i, 1) as $d) {
echo $d->format('Y-m-d H:i:s') . "\n";
}
?>
Will output:
2010-11-03 12:41:05
2010-11-04 12:41:05
When you add the time 23:59:59 to the end DateTime object something like the following then the end date will be included in the period:
<?php
$date_start = new DateTime('2012-03-12');
$date_end = new DateTime('2012-03-22 23:59:59');
$interval = '+2 days';
$date_interval = DateInterval::createFromDateString($interval);
$period = new DatePeriod($date_start, $date_interval, $date_end, DatePeriod::EXCLUDE_START_DATE);
foreach($period as $dt) {
echo $dt->format('d/m');
}
?>
OUTPUT:
14/03
16/03
18/03
20/03
22/03
The parameter isostr should accept an ISO 8601 format, but doing this is not work :
<?php
$dateStart = date_create('first day of next month this year');
$isoStr = $dateStart ->format(DateTimeInterface::ISO8601);
$datePeriod = new DatePeriod("R10/{$isoStr}/P1M");
// Throw Exception : DatePeriod::__construct(): Unknown or bad format (R10/2020-02-01T22:52:26+0000Z/P1M)
// While doing it by this way works
$datePeriod = new DatePeriod($dateStart , DateInterval::createFromDateString("+1 month"), 10);
?>
With reference to the Changelog above, 'recurrences' must be greater than 0 now.
This was not the case in PHP5 ( >= 5.3.0). A foreach loop over a DatePeriod with recurrences == 0 would
execute one time. A function could accept a $count parameter which represented the number of times to execute
the code in a foreach loop, and then initialize a DatePeriod with 'recurrences' == ($count-1) to get the desired
number of iterations.
The following example adds a special case for PHP7 and above to handle the situation where a single
iteration is desired.
Note that an alternative solution to subracting 1 from the desired count is to subtract one month from the desired starting month,
and then intialize the DatePeriod with the option DatePeriod::EXCLUDE_START_DATE.
<?php
// displayCalender() is a stub.
// In a real application, this would generate a displayable calendar for the specified month.
//
// $tp is a DateTime object used to specify the month for which a calendar will be displayed
function displayCalendar($tp)
{
$format = "F, Y";
echo "Display Calendar for " . $tp->format($format) . "\n";
}
// $date is the first month to show
// $count is the number of months to show
// NOTE: the number of "recurrences" is one less than the number of months to display
function showMonths($date = false, $count = 1)
{
$format = "Y-m-d 00:00:00";
$init = ($date ? $date : date($format));
$one_month = new DateInterval("P1M");
// get the starting month and day
$start = new DateTime($init);
echo "Show $count month" . ($count > 1 ? "s" : "") . "\n";
//check for PHP7 or greater
if ($count == 1 && (substr(phpversion(), 0, 1) >= 7) )
{
// Special case for PHP7 when $count == 1
displayCalendar($start);
}
else
{
// PHP5 does not need special case, because 0 is accepted value
// for number of recurrences
$time_period = new DatePeriod($start, $one_month, ($count-1));
foreach ($time_period as $tp)
{
displayCalendar($tp);
}
}
echo "\n";
}
// Show calendar for specific month
$first_month = "2021-11";
showMonths($first_month);
// Show calendars for a full year
$first_month = "2021-01";
showMonths($first_month, 12);
?>
The above example will output:
Show 1 month
Display Calendar for November, 2021
Show 12 months
Display Calendar for January, 2021
Display Calendar for February, 2021
Display Calendar for March, 2021
Display Calendar for April, 2021
Display Calendar for May, 2021
Display Calendar for June, 2021
Display Calendar for July, 2021
Display Calendar for August, 2021
Display Calendar for September, 2021
Display Calendar for October, 2021
Display Calendar for November, 2021
Display Calendar for December, 2021