[wp-hackers] Date/Time and WP

[Ryan McCue]

Dobri wrote:
> That makes sense. So, would you say there are performance benefits to using DateTime and the function you provided to just using date_i18n as William suggested? And is this a more robust method (for now) because of the bug in core that Alex brought up when dealing with date/time in DLS while it's currently not DLS and vice versa?

If you're working with relative time, you should definitely be using the
DateTime and DateTimeZone classes. DateTime natively understands
DateTimeZone and the DST transitions that can occur with it.

Performance-wise, creating a DateTimeZone instance is costly, but using
DateTime is fairly fast. If you're using this in production, I'd
recommend caching it:

protected function get_timezone() {
	static $zone = null;
	if ($zone !== null)
		return $zone;

	$tzstring = get_option( 'timezone_string' );
	if ( ! $tzstring ) {
		// Create a UTC+- zone if no timezone string exists
		$current_offset = get_option( 'gmt_offset' );
		if ( 0 == $current_offset )
			$tzstring = 'UTC';
		elseif ($current_offset < 0)
			$tzstring = 'Etc/GMT' . $current_offset;
		else
			$tzstring = 'Etc/GMT+' . $current_offset;
	}
	$zone = new DateTimeZone( $tzstring );
	return $zone;
}

(I'm using this in my JSON REST API, and the caching is fairly important
when using this for a list of posts.)

-- 
Ryan McCue
<http://ryanmccue.info/>