DateTimeZone::getOffset

timezone_offset_get

(PHP 5 >= 5.2.0)

DateTimeZone::getOffset -- timezone_offset_get — Returns the timezone offset from GMT

说明

面向对象风格

public int DateTimeZone::getOffset ( DateTime $datetime )

过程化风格

int timezone_offset_get ( DateTimeZone $object , DateTime $datetime )

This function returns the offset to GMT for the date/time specified in the datetime parameter. The GMT offset is calculated with the timezone information contained in the DateTimeZone object being used.

参数

object: 仅过程化风格：由 timezone_open() 返回的 DateTimeZone 对象。
datetime: DateTime that contains the date/time to compute the offset from.

返回值

Returns time zone offset in seconds on success 或者在失败时返回 FALSE.

范例

Example #1 DateTimeZone::getOffset() examples


<?php
// Create two timezone objects, one for Taipei (Taiwan) and one for
// Tokyo (Japan)
$dateTimeZoneTaipei = new DateTimeZone("Asia/Taipei");
$dateTimeZoneJapan = new DateTimeZone("Asia/Tokyo");

// Create two DateTime objects that will contain the same Unix timestamp, but
// have different timezones attached to them.
$dateTimeTaipei = new DateTime("now", $dateTimeZoneTaipei);
$dateTimeJapan = new DateTime("now", $dateTimeZoneJapan);

// Calculate the GMT offset for the date/time contained in the $dateTimeTaipei
// object, but using the timezone rules as defined for Tokyo
// ($dateTimeZoneJapan).
$timeOffset = $dateTimeZoneJapan->getOffset($dateTimeTaipei);

// Should show int(32400) (for dates after Sat Sep 8 01:00:00 1951 JST).
var_dump($timeOffset);
?>

PHP手册 - N: Returns the timezone offset from GMT

用户评论:

skanzow at gmx dot net (08-Sep-2011 02:55)

A common problem is to format dates and times for XML documents. The XML standard is defined as follows: " To specify a time zone, you can either enter a dateTime in UTC time by adding a "Z" behind the time - like this: <startdate>2002-05-30T09:30:10Z</startdate> or you can specify an offset from the UTC time by adding a positive or negative time behind the time - like this: <startdate>2002-05-30T09:30:10-06:00</startdate> " Here is a possible solution in PHP: <?php if(date_default_timezone_get() == 'UTC') { $offsetString = 'Z'; // No need to calculate offset, as default timezone is already UTC } else { $phpTime = '2002-05-30 09:30:10'; $millis = strtotime($phpTime); // Convert time to milliseconds since 1970, using default timezone $timezone = new DateTimeZone(date_default_timezone_get()); // Get default system timezone to create a new DateTimeZone object $offset = $timezone->getOffset(new DateTime($phpTime)); // Offset in seconds to UTC $offsetHours = round(abs($offset)/3600); $offsetMinutes = round((abs($offset) - $offsetHours * 3600) / 60); $offsetString = ($offset < 0 ? '-' : '+') . ($offsetHours < 10 ? '0' : '') . $offsetHours . ':' . ($offsetMinutes < 10 ? '0' : '') . $offsetMinutes; } echo('<startdate>' . date('Y-m-d\TH:i:s', $millis) . $offsetString . '</startdate>'); // This is the correct XML format ?>