IntlCalendar::roll

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

IntlCalendar::roll — Add value to field without carrying into more significant fields

说明

面向对象风格

public IntlCalendar::roll(int $field, int|bool $value): bool

过程化风格

intlcal_roll(IntlCalendar $calendar, int $field, int|bool $value): bool

Adds a (signed) amount to a field. The difference with respect to IntlCalendar::add() is that when the field value overflows, it does not carry into more significant fields.

参数

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 field, true for rolling up (adding 1), or false for rolling down (subtracting 1).

返回值

Returns true on success or false on failure.

范例

示例 #1 IntlCalendar::roll()

<?php
ini_set('date.timezone', 'Europe/Lisbon');
ini_set('intl.default_locale', 'pt_PT');

$cal = new IntlGregorianCalendar(2013, 5 /* June */, 30);

$cal->add(IntlCalendar::FIELD_DAY_OF_MONTH, 1);
var_dump(IntlDateFormatter::formatObject($cal)); // "01/07/2013, 00:00:00"

$cal->set(2013, 5 /* June */, 30);
$cal->roll(IntlCalendar::FIELD_DAY_OF_MONTH, true); // roll up, same as rolling +1
var_dump(IntlDateFormatter::formatObject($cal)); // "01/06/2013, 00:00:00"

以上例程会输出：

string(20) "01/07/2013, 00:00:00"
string(20) "01/06/2013, 00:00:00"

参见