wp_timezone_choice( string $selected_zone, string $locale = null ): string

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$selected_zonestring

Selected timezone.

$localestringoptional

Locale to load the timezones in. Default current site locale.Default: null

Return value

string

Performance profile

How much work a call to wp_timezone_choice() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Heavy

Reads stored settings via get_site_option(), cached per request but not free on a cold cache.

Scaling

Scales with input

The body loops, so the work grows with what you pass in.

Instructions

81–111

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 328.

Plugin surface

None

Nothing here hands control to plugin code.

Called by

0

Nothing in core calls this; the cost is only what you spend yourself.

What it touches

• hookthird-party callbacksapply_filters()one call below wp_timezone_choice()
• optionnetwork optionget_site_option()one call below wp_timezone_choice()

Further down the call graph this can also reach cache, serialize, query and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.

What one call costs · 12 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_timezone_choice() can have, taken from its control-flow graph on PHP 8.5.

This body has more branch combinations than are worth enumerating, so the table covers the outcomes found first rather than every one that exists.

Uses · 8

• get_locale()Retrieves the current locale.
• unload_textdomain()Unloads translations for a text domain.
• load_textdomain()Loads a .mo file into the text domain $domain.
• translate()Retrieves the translation of $text.
• __()Retrieves the translation of $text.
• esc_attr()Escaping for HTML attributes.
• esc_html()Escaping for HTML blocks.
• esc_attr__()Retrieves the translation of $text and escapes it for safe use in an attribute.

Source code

View on Trac ↗View on GitHub ↗

6613function wp_timezone_choice( $selected_zone, $locale = null ) {6614	static $mo_loaded = false, $locale_loaded = null;6615 6616	$continents = array( 'Africa', 'America', 'Antarctica', 'Arctic', 'Asia', 'Atlantic', 'Australia', 'Europe', 'Indian', 'Pacific' );6617 6618	// Load translations for continents and cities.6619	if ( ! $mo_loaded || $locale !== $locale_loaded ) {6620		$locale_loaded = $locale ? $locale : get_locale();6621		$mofile        = WP_LANG_DIR . '/continents-cities-' . $locale_loaded . '.mo';6622		unload_textdomain( 'continents-cities', true );6623		load_textdomain( 'continents-cities', $mofile, $locale_loaded );6624		$mo_loaded = true;6625	}6626 6627	$tz_identifiers = timezone_identifiers_list();6628	$zonen          = array();6629 6630	foreach ( $tz_identifiers as $zone ) {6631		$zone = explode( '/', $zone );6632		if ( ! in_array( $zone[0], $continents, true ) ) {6633			continue;6634		}6635 6636		// This determines what gets set and translated - we don't translate Etc/* strings here, they are done later.6637		$exists    = array(6638			0 => ( isset( $zone[0] ) && $zone[0] ),6639			1 => ( isset( $zone[1] ) && $zone[1] ),6640			2 => ( isset( $zone[2] ) && $zone[2] ),6641		);6642		$exists[3] = ( $exists[0] && 'Etc' !== $zone[0] );6643		$exists[4] = ( $exists[1] && $exists[3] );6644		$exists[5] = ( $exists[2] && $exists[3] );6645 6646		// phpcs:disable WordPress.WP.I18n.LowLevelTranslationFunction,WordPress.WP.I18n.NonSingularStringLiteralText6647		$zonen[] = array(6648			'continent'   => ( $exists[0] ? $zone[0] : '' ),6649			'city'        => ( $exists[1] ? $zone[1] : '' ),6650			'subcity'     => ( $exists[2] ? $zone[2] : '' ),6651			't_continent' => ( $exists[3] ? translate( str_replace( '_', ' ', $zone[0] ), 'continents-cities' ) : '' ),6652			't_city'      => ( $exists[4] ? translate( str_replace( '_', ' ', $zone[1] ), 'continents-cities' ) : '' ),6653			't_subcity'   => ( $exists[5] ? translate( str_replace( '_', ' ', $zone[2] ), 'continents-cities' ) : '' ),6654		);6655		// phpcs:enable6656	}6657	usort( $zonen, '_wp_timezone_choice_usort_callback' );6658 6659	$structure = array();6660 6661	if ( empty( $selected_zone ) ) {6662		$structure[] = '<option selected="selected" value="">' . __( 'Select a city' ) . '</option>';6663	}6664 6665	// If this is a deprecated, but valid, timezone string, display it at the top of the list as-is.6666	if ( in_array( $selected_zone, $tz_identifiers, true ) === false6667		&& in_array( $selected_zone, timezone_identifiers_list( DateTimeZone::ALL_WITH_BC ), true )6668	) {6669		$structure[] = '<option selected="selected" value="' . esc_attr( $selected_zone ) . '">' . esc_html( $selected_zone ) . '</option>';6670	}6671 6672	foreach ( $zonen as $key => $zone ) {6673		// Build value in an array to join later.6674		$value = array( $zone['continent'] );6675 6676		if ( empty( $zone['city'] ) ) {6677			// It's at the continent level (generally won't happen).6678			$display = $zone['t_continent'];6679		} else {6680			// It's inside a continent group.6681 6682			// Continent optgroup.6683			if ( ! isset( $zonen[ $key - 1 ] ) || $zonen[ $key - 1 ]['continent'] !== $zone['continent'] ) {6684				$label       = $zone['t_continent'];6685				$structure[] = '<optgroup label="' . esc_attr( $label ) . '">';6686			}6687 6688			// Add the city to the value.6689			$value[] = $zone['city'];6690 6691			$display = $zone['t_city'];6692			if ( ! empty( $zone['subcity'] ) ) {

Changelog

Introduced in 2.9.0. Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 6.7.7 tag, from src/wp-includes/functions.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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