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DateInterval::__construct

PHP function Edit on GitHub ✎

(PHP 5 >= 5.3.0, PHP 7, PHP 8)

Creates a new DateInterval object

Description

DateInterval::__construct(string $duration)

Creates a new DateInterval object.

Parameters

duration

An interval specification.

The format starts with the letter P, for period. Each duration period is represented by an integer value followed by a period designator. If the duration contains time elements, that portion of the specification is preceded by the letter T.

Period Designator	Description
`Y`	years
`M`	months
`D`	days
`W`	weeks. Converted into days. Prior to PHP 8.0.0, can not be combined with `D`.
`H`	hours
`M`	minutes
`S`	seconds

Here are some simple examples. Two days is P2D. Two seconds is PT2S. Six years and five minutes is P6YT5M.

Note

The unit types must be entered from the largest scale unit on the left to the smallest scale unit on the right. So years before months, months before days, days before minutes, etc. Thus one year and four days must be represented as P1Y4D, not P4D1Y.

The specification can also be represented as a date time. A sample of one year and four days would be P0001-00-04T00:00:00. But the values in this format can not exceed a given period's roll-over-point (e.g. 25 hours is invalid).

These formats are based on the ISO 8601 duration specification.

Errors/Exceptions

Throws an DateMalformedIntervalStringException when the duration cannot be parsed as an interval. Prior to PHP 8.3, this was Exception.

Changelog

Version	Description
8.3.0	Now throws `DateMalformedIntervalStringException` instead of `Exception`.
8.2.0	Only the `y` to `f`, `invert`, and `days` will be visible, including a new `from_string` boolean property.
8.0.0	`W` can be combined with `D`.

Examples

Constructing and using DateInterval objects

php

<?php
// Create a specific date
$someDate = \DateTime::createFromFormat("Y-m-d H:i", "2022-08-25 14:18");

// Create interval
$interval = new \DateInterval("P7D");

// Add interval
$someDate->add($interval);

// Convert interval to string
echo $interval->format("%d");

The above example will output:

output

DateInterval example

php

<?php
$interval = new DateInterval('P1W2D');
var_dump($interval);

output

object(DateInterval)#1 (10) {
  ["y"]=>
  int(0)
  ["m"]=>
  int(0)
  ["d"]=>
  int(9)
  ["h"]=>
  int(0)
  ["i"]=>
  int(0)
  ["s"]=>
  int(0)
  ["f"]=>
  float(0)
  ["invert"]=>
  int(0)
  ["days"]=>
  bool(false)
  ["from_string"]=>
  bool(false)
}

output

object(DateInterval)#1 (16) {
  ["y"]=>
  int(0)
  ["m"]=>
  int(0)
  ["d"]=>
  int(9)
  ["h"]=>
  int(0)
  ["i"]=>
  int(0)
  ["s"]=>
  int(0)
  ["f"]=>
  float(0)
  ["weekday"]=>
  int(0)
  ["weekday_behavior"]=>
  int(0)
  ["first_last_day_of"]=>
  int(0)
  ["invert"]=>
  int(0)
  ["days"]=>
  bool(false)
  ["special_type"]=>
  int(0)
  ["special_amount"]=>
  int(0)
  ["have_weekday_relative"]=>
  int(0)
  ["have_special_relative"]=>
  int(0)
}

output

object(DateInterval)#1 (16) {
  ["y"]=>
  int(0)
  ["m"]=>
  int(0)
  ["d"]=>
  int(2)
  ["h"]=>
  int(0)
  ["i"]=>
  int(0)
  ["s"]=>
  int(0)
  ["f"]=>
  float(0)
  ["weekday"]=>
  int(0)
  ["weekday_behavior"]=>
  int(0)
  ["first_last_day_of"]=>
  int(0)
  ["invert"]=>
  int(0)
  ["days"]=>
  bool(false)
  ["special_type"]=>
  int(0)
  ["special_amount"]=>
  int(0)
  ["have_weekday_relative"]=>
  int(0)
  ["have_special_relative"]=>
  int(0)
}

DateInterval::__construct

Description

Parameters

Errors/Exceptions

Changelog

Examples

See Also