PHP Manual
DateInterval
Creates a new DateInterval object

DateInterval::__construct

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

DateInterval::__construct — Creates a new DateInterval object

Description

public 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.

**`duration` Period Designators**
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 Exception when the duration cannot be parsed as an interval.

Changelog

Version	Description
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

Example #1 DateInterval example


<?php

$interval = new DateInterval('P1W2D');
var_dump($interval);

?>

Output of the above example in PHP 8.2:

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 of the above example in PHP 8:

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 of the above example in PHP 7:

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)
}