date_default_timezone_get - PHP code example

PHP Function Date_Default_Timezone_Get

Dealing with timezones is a vital aspect of working with date and time functions in any web application. Setting the default timezone correctly ensures that your application accurately represents dates and times based on the user's location. The default timezone should be set as early as possible in your script, preferably at the very beginning, and should be a valid timezone string (such as "America/New_York" or "Europe/Rome") - for more information see PHP documentation.

The php function date_default_timezone_get is used to get the default time zone that is used by all the date and time functions in your script. It accepts one argument, which is the default time zone. If this argument is not set, the function will return a default value of UTC. It also returns False if the timezone identifier is invalid or True if it has been set.

This function is available starting with PHP Version 5.1.0 and works on all later versions of PHP. It was previously possible to read the default timezone by reading the TZ environment variable, but this is now deprecated and the php function date_default_timezone_get should be used instead.

To demonstrate how this function is used, we have created a simple example script. The first line of the script sets the default timezone to 'UTC' and then calls the date_default_timezone_get function two more times, once before setting the timezone and again after it has been set. The result is shown below.

date_default_timezone_get example

use Symfony\Component\HttpKernel\Attribute\MapDateTime;
use Symfony\Component\HttpKernel\Controller\ArgumentResolver\DateTimeValueResolver;
use Symfony\Component\HttpKernel\ControllerMetadata\ArgumentMetadata;
use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;

class DateTimeValueResolverTest extends TestCase
{
    private readonly string $defaultTimezone;

    protected function setUp(): void
    {
        $this->defaultTimezone = date_default_timezone_get();
    }

    protected function tearDown(): void
    {
        date_default_timezone_set($this->defaultTimezone);
    }

    public static function getTimeZones()
    {
        yield ['UTC', false];
        yield ['Pacific/Honolulu', false];

    use ExpectDeprecationTrait;

    public const TESTED_TYPE = 'Symfony\Component\Form\Extension\Core\Type\DateType';

    private string $defaultTimezone;
    private string $defaultLocale;

    protected function setUp(): void
    {
        parent::setUp();
        $this->defaultTimezone = date_default_timezone_get();
        $this->defaultLocale = \Locale::getDefault();
    }

    protected function tearDown(): void
    {
        date_default_timezone_set($this->defaultTimezone);
        \Locale::setDefault($this->defaultLocale);
    }

    public function testInvalidWidgetOption()
    {

  public function providerTestDateTimezone() {
    // Use a common date for most of the tests.     $date_string = '2007-01-31 21:00:00';

    // Detect the system timezone.     $system_timezone = date_default_timezone_get();

    return [
      // Create a date object with an unspecified timezone, which should       // end up using the system timezone.       [$date_string, NULL, $system_timezone, 'DateTimePlus uses the system timezone when there is no site timezone.'],
      // Create a date object with a specified timezone name.       [$date_string, 'America/Yellowknife', 'America/Yellowknife', 'DateTimePlus uses the specified timezone if provided.'],
      // Create a date object with a timezone object.       [$date_string, new \DateTimeZone('Australia/Canberra'), 'Australia/Canberra', 'DateTimePlus uses the specified timezone if provided.'],
      // Create a date object with another date object.       [new DateTimePlus('now', 'Pacific/Midway'), NULL, 'Pacific/Midway', 'DateTimePlus uses the specified timezone if provided.'],
    ];

class DateTimeWidgetBase extends WidgetBase {

  /** * {@inheritdoc} */
  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
    $element['value'] = [
      '#type' => 'datetime',
      '#default_value' => NULL,
      '#date_increment' => 1,
      '#date_timezone' => date_default_timezone_get(),
      '#required' => $element['#required'],
    ];

    if ($this->getFieldSetting('datetime_type') == DateTimeItem::DATETIME_TYPE_DATE) {
      // A date-only field should have no timezone conversion performed, so       // use the same timezone as for storage.       $element['value']['#date_timezone'] = DateTimeItemInterface::STORAGE_TIMEZONE;
    }

    if ($items[$delta]->date) {
      $element['value']['#default_value'] = $this->createDefaultValue($items[$delta]->date, $element['value']['#date_timezone']);
    }

  public function testBootKernel() {
    $this->assertNull($this->container->get('request_stack')->getParentRequest(), 'There should only be one request on the stack');
    $this->assertEquals('public', \Drupal::config('system.file')->get('default_scheme'));
  }

  /** * Tests the assumption that local time is in 'Australia/Sydney'. */
  public function testLocalTimeZone() {
    // The 'Australia/Sydney' time zone is set in core/tests/bootstrap.php     $this->assertEquals('Australia/Sydney', date_default_timezone_get());
  }

  /** * Tests that a test method is skipped when it requires a module not present. * * In order to catch checkRequirements() regressions, we have to make a new * test object and run checkRequirements() here. * * @covers ::checkRequirements * @covers ::checkModuleRequirements */

  /** * Overrides prepareTimezone(). * * Override basic component timezone handling to use Drupal's * knowledge of the preferred user timezone. */
  protected function prepareTimezone($timezone) {
    if (empty($timezone)) {
      // Fallback to user or system default timezone.       $timezone = date_default_timezone_get();
    }
    return parent::prepareTimezone($timezone);
  }

  /** * Overrides format(). * * @param string $format * A format string using either PHP's date(). * @param array $settings * - timezone: (optional) String timezone name. Defaults to the timezone * of the date object. * - langcode: (optional) String two letter language code used to control * the result of the format() method. Defaults to NULL. * * @return string * The formatted value of the date. Since the format may contain user input, * this value should be escaped when output. */

class DateCasterTest extends TestCase
{
    use VarDumperTestTrait;

    private string $previousTimezone;

    protected function setUp(): void
    {
        parent::setUp();

        $this->previousTimezone = date_default_timezone_get();
    }

    protected function tearDown(): void
    {
        parent::tearDown();

        date_default_timezone_set($this->previousTimezone);
    }

    /** * @dataProvider provideDateTimes */

$databaseZone = new DateTimeZone($timeZone);
            } else {
                $timeZoneFromAbbr = timezone_name_from_abbr($timeZone);
                if (\is_string($timeZoneFromAbbr)) {
                    $databaseZone = timezone_open($timeZoneFromAbbr);
                    if (!$databaseZone instanceof DateTimeZone) {
                        $databaseZone = null;
                    }
                }
            }

            $phpZone = timezone_open(date_default_timezone_get());
            if ($databaseZone instanceof DateTimeZone && $phpZone instanceof DateTimeZone) {
                $databaseTime = new DateTime('now', $databaseZone);
                $offset = abs($databaseZone->getOffset(new DateTime()) - $phpZone->getOffset($databaseTime));
            }
        }

        if (empty($offset)) {
            $sql = 'SELECT UNIX_TIMESTAMP()-' . time();
            $offset = (int) $connection->executeQuery($sql)->fetchOne();
        }

/** * Returns UTC timestamp of user's TZ 'now'. * * The date field stores date_only values without conversion, considering them * already as UTC. This method returns the UTC equivalent of user's 'now' as a * unix timestamp, so they match using Y-m-d format. * * @return int * Unix timestamp. */
  protected function getUTCEquivalentOfUserNowAsTimestamp() {
    $user_now = new DateTimePlus('now', new \DateTimeZone(date_default_timezone_get()));
    $utc_equivalent = new DateTimePlus($user_now->format('Y-m-d H:i:s'), new \DateTimeZone(DateTimeItemInterface::STORAGE_TIMEZONE));

    return $utc_equivalent->getTimestamp();
  }

  /** * Returns an array formatted date_only values relative to timestamp. * * @param int $timestamp * Unix Timestamp used as 'today'. * * @return array * An array of DateTimeItemInterface::DATE_STORAGE_FORMAT date values. In * order tomorrow, today and yesterday. */

'symfony_version' => Kernel::VERSION,
            'symfony_minor_version' => sprintf('%s.%s', Kernel::MAJOR_VERSION, Kernel::MINOR_VERSION),
            'symfony_lts' => 4 === Kernel::MINOR_VERSION,
            'symfony_state' => $this->determineSymfonyState(),
            'symfony_eom' => $eom->format('F Y'),
            'symfony_eol' => $eol->format('F Y'),
            'env' => isset($this->kernel) ? $this->kernel->getEnvironment() : 'n/a',
            'debug' => isset($this->kernel) ? $this->kernel->isDebug() : 'n/a',
            'php_version' => \PHP_VERSION,
            'php_architecture' => \PHP_INT_SIZE * 8,
            'php_intl_locale' => class_exists(\Locale::class, false) && \Locale::getDefault() ? \Locale::getDefault() : 'n/a',
            'php_timezone' => date_default_timezone_get(),
            'xdebug_enabled' => \extension_loaded('xdebug'),
            'apcu_enabled' => \extension_loaded('apcu') && filter_var(\ini_get('apc.enabled'), \FILTER_VALIDATE_BOOL),
            'zend_opcache_enabled' => \extension_loaded('Zend OPcache') && filter_var(\ini_get('opcache.enable'), \FILTER_VALIDATE_BOOL),
            'bundles' => [],
            'sapi_name' => \PHP_SAPI,
        ];

        if (isset($this->kernel)) {
            foreach ($this->kernel->getBundles() as $name => $bundle) {
                $this->data['bundles'][$name] = new ClassStub($bundle::class);
            }
        }

// Ensure the update module is not installed.     $this->assertFalse(\Drupal::moduleHandler()->moduleExists('update'), 'The Update module is not installed.');
  }

  /** * Tests the assumption that local time is in 'Australia/Sydney'. */
  public function testLocalTimeZone() {
    $expected = 'Australia/Sydney';
    // The 'Australia/Sydney' time zone is set in core/tests/bootstrap.php     $this->assertEquals($expected, date_default_timezone_get());

    // The 'Australia/Sydney' time zone is also set in     // FunctionalTestSetupTrait::initConfig().     $config_factory = $this->container->get('config.factory');
    $value = $config_factory->get('system.date')->get('timezone.default');
    $this->assertEquals($expected, $value);

    // Test that users have the correct time zone set.     $this->assertEquals($expected, $this->rootUser->getTimeZone());
    $admin_user = $this->drupalCreateUser(['administer site configuration']);
    $this->assertEquals($expected, $admin_user->getTimeZone());
  }

  public static function getLabel() {
    return t("Time zone");
  }

  /** * {@inheritdoc} */
  public function getContext() {
    // date_default_timezone_set() is called in AccountProxy::setAccount(), so     // we can safely retrieve the timezone.     return date_default_timezone_get();
  }

  /** * {@inheritdoc} */
  public function getCacheableMetadata() {
    return new CacheableMetadata();
  }

}

        $this->restoreDefaultTimezone();

        \Locale::setDefault($this->defaultLocale);
    }

    protected function setDefaultTimezone(?string $defaultTimezone)
    {
        // Make sure this method cannot be called twice before calling         // also restoreDefaultTimezone()         if (null === $this->defaultTimezone) {
            $this->defaultTimezone = date_default_timezone_get();
            date_default_timezone_set($defaultTimezone);
        }
    }

    protected function restoreDefaultTimezone()
    {
        if (null !== $this->defaultTimezone) {
            date_default_timezone_set($this->defaultTimezone);
            $this->defaultTimezone = null;
        }
    }

else if ($part !== self::TIMESTAMP) {
                $date = self::now($locale);
                $date = $date->get($part);
            }
        }

        if (parent::$_defaultOffset != 0) {
            $date = $this->_getTime(parent::$_defaultOffset);
        }

        // set the timezone and offset for $this         $zone = @date_default_timezone_get();
        $this->setTimezone($zone);

        // try to get timezone from date-string         if (!is_int($date)) {
            $zone = $this->getTimezoneFromString($date);
            $this->setTimezone($zone);
        }

        // set datepart         if (($part !== null && $part !== self::TIMESTAMP) or (!is_numeric($date))) {
            // switch off dst handling for value setting

protected $outputTimezone;

    /** * @param string|null $inputTimezone The name of the input timezone * @param string|null $outputTimezone The name of the output timezone * * @throws InvalidArgumentException if a timezone is not valid */
    public function __construct(string $inputTimezone = null, string $outputTimezone = null)
    {
        $this->inputTimezone = $inputTimezone ?: date_default_timezone_get();
        $this->outputTimezone = $outputTimezone ?: date_default_timezone_get();

        // Check if input and output timezones are valid         try {
            new \DateTimeZone($this->inputTimezone);
        } catch (\Exception $e) {
            throw new InvalidArgumentException(sprintf('Input timezone is invalid: "%s".', $this->inputTimezone), $e->getCode(), $e);
        }

        try {
            new \DateTimeZone($this->outputTimezone);
        }