IntlCalendar::add

(PHP 5 >= 5.5.0, PHP 7, PHP 8, PECL >= 3.0.0a1)

IntlCalendar::addAdd a (signed) amount of time to a field

Description

Object-oriented style

public IntlCalendar::add(int $field, int $value): bool

Procedural style

intlcal_add(IntlCalendar $calendar, int $field, int $value): bool

Add a signed amount to a field. Adding a positive amount allows advances in time, even if the numeric value of the field decreases (e.g. when working with years in BC dates).

Other fields may need to adjusted – for instance, adding a month to the 31st of January will result in the 28th (or 29th) of February. Contrary to IntlCalendar::roll(), when a value wraps around, more significant fields may change. For instance, adding a day to the 31st of January will result in the 1st of February, not the 1st of January.

Parameters

calendar

An IntlCalendar instance.

field

One of the IntlCalendar date/time field constants. These are integer values between 0 and IntlCalendar::FIELD_COUNT.

value

The signed amount to add to the current field. If the amount is positive, the instant will be moved forward; if it is negative, the instant will be moved into the past. The unit is implicit to the field type. For instance, hours for IntlCalendar::FIELD_HOUR_OF_DAY.

Return Values

Returns true on success or false on failure.

Examples

Example #1 IntlCalendar::add()

<?php
ini_set
('intl.default_locale''fr_FR');
ini_set('date.timezone''UTC');

$cal = new IntlGregorianCalendar(2012/* January */31);
echo 
IntlDateFormatter::formatObject($cal), "\n";

$cal->add(IntlCalendar::FIELD_MONTH1);
echo 
IntlDateFormatter::formatObject($cal), "\n";

$cal->add(IntlCalendar::FIELD_DAY_OF_MONTH1);
echo 
IntlDateFormatter::formatObject($cal), "\n";

The above example will output:

31 janv. 2012 00:00:00
29 févr. 2012 00:00:00
1 mars 2012 00:00:00