As the sun rises and the forest mist clears, and the clouds return and the caves darken, these changes of light and shadow are the morning and evening in the mountains. Wildflowers bloom with their subtle fragrance, fine trees flourish with their dense shade, the wind and frost are pure and clean, and the water recedes to reveal the rocks—these are the four seasons in the mountains. Going out in the morning and returning in the evening, the scenery of the four seasons is different, and the joy is endless.至于负者歌于途,行者休于树,前者呼,后者应,伛偻提携,往来而不绝者,滁人游也。临溪而渔,溪深而鱼肥,酿泉为酒,泉香而酒洌,山肴野蔌,杂然而前陈者,太守宴也。宴酣之乐,非丝非竹,射者中,弈者胜,觥筹交错,起坐而喧哗者,众宾欢也。苍颜白发,颓然乎其间者,太守醉也。
<?php
/**
* Locale API: WP_Locale_Switcher class
*
* @package WordPress
* @subpackage i18n
* @since 4.7.0
*/
/**
* Core class used for switching locales.
*
* @since 4.7.0
*/
#[AllowDynamicProperties]
class WP_Locale_Switcher {
/**
* Locale switching stack.
*
* @since 6.2.0
* @var array
*/
private $stack = array();
/**
* Original locale.
*
* @since 4.7.0
* @var string
*/
private $original_locale;
/**
* Holds all available languages.
*
* @since 4.7.0
* @var string[] An array of language codes (file names without the .mo extension).
*/
private $available_languages;
/**
* Constructor.
*
* Stores the original locale as well as a list of all available languages.
*
* @since 4.7.0
*/
public function __construct() {
$this->original_locale = determine_locale();
$this->available_languages = array_merge( array( 'en_US' ), get_available_languages() );
}
/**
* Initializes the locale switcher.
*
* Hooks into the {@see 'locale'} and {@see 'determine_locale'} filters
* to change the locale on the fly.
*
* @since 4.7.0
*/
public function init() {
add_filter( 'locale', array( $this, 'filter_locale' ) );
add_filter( 'determine_locale', array( $this, 'filter_locale' ) );
}
/**
* Switches the translations according to the given locale.
*
* @since 4.7.0
*
* @param string $locale The locale to switch to.
* @param int|false $user_id Optional. User ID as context. Default false.
* @return bool True on success, false on failure.
*/
public function switch_to_locale( $locale, $user_id = false ) {
$current_locale = determine_locale();
if ( $current_locale === $locale ) {
return false;
}
if ( ! in_array( $locale, $this->available_languages, true ) ) {
return false;
}
$this->stack[] = array( $locale, $user_id );
$this->change_locale( $locale );
/**
* Fires when the locale is switched.
*
* @since 4.7.0
* @since 6.2.0 The `$user_id` parameter was added.
*
* @param string $locale The new locale.
* @param false|int $user_id User ID for context if available.
*/
do_action( 'switch_locale', $locale, $user_id );
return true;
}
/**
* Switches the translations according to the given user's locale.
*
* @since 6.2.0
*
* @param int $user_id User ID.
* @return bool True on success, false on failure.
*/
public function switch_to_user_locale( $user_id ) {
$locale = get_user_locale( $user_id );
return $this->switch_to_locale( $locale, $user_id );
}
/**
* Restores the translations according to the previous locale.
*
* @since 4.7.0
*
* @return string|false Locale on success, false on failure.
*/
public function restore_previous_locale() {
$previous_locale = array_pop( $this->stack );
if ( null === $previous_locale ) {
// The stack is empty, bail.
return false;
}
$entry = end( $this->stack );
$locale = is_array( $entry ) ? $entry[0] : false;
if ( ! $locale ) {
// There's nothing left in the stack: go back to the original locale.
$locale = $this->original_locale;
}
$this->change_locale( $locale );
/**
* Fires when the locale is restored to the previous one.
*
* @since 4.7.0
*
* @param string $locale The new locale.
* @param string $previous_locale The previous locale.
*/
do_action( 'restore_previous_locale', $locale, $previous_locale[0] );
return $locale;
}
/**
* Restores the translations according to the original locale.
*
* @since 4.7.0
*
* @return string|false Locale on success, false on failure.
*/
public function restore_current_locale() {
if ( empty( $this->stack ) ) {
return false;
}
$this->stack = array( array( $this->original_locale, false ) );
return $this->restore_previous_locale();
}
/**
* Whether switch_to_locale() is in effect.
*
* @since 4.7.0
*
* @return bool True if the locale has been switched, false otherwise.
*/
public function is_switched() {
return ! empty( $this->stack );
}
/**
* Returns the locale currently switched to.
*
* @since 6.2.0
*
* @return string|false Locale if the locale has been switched, false otherwise.
*/
public function get_switched_locale() {
$entry = end( $this->stack );
if ( $entry ) {
return $entry[0];
}
return false;
}
/**
* Returns the user ID related to the currently switched locale.
*
* @since 6.2.0
*
* @return int|false User ID if set and if the locale has been switched, false otherwise.
*/
public function get_switched_user_id() {
$entry = end( $this->stack );
if ( $entry ) {
return $entry[1];
}
return false;
}
/**
* Filters the locale of the WordPress installation.
*
* @since 4.7.0
*
* @param string $locale The locale of the WordPress installation.
* @return string The locale currently being switched to.
*/
public function filter_locale( $locale ) {
$switched_locale = $this->get_switched_locale();
if ( $switched_locale ) {
return $switched_locale;
}
return $locale;
}
/**
* Load translations for a given locale.
*
* When switching to a locale, translations for this locale must be loaded from scratch.
*
* @since 4.7.0
*
* @global Mo[] $l10n An array of all currently loaded text domains.
*
* @param string $locale The locale to load translations for.
*/
private function load_translations( $locale ) {
global $l10n;
$domains = $l10n ? array_keys( $l10n ) : array();
load_default_textdomain( $locale );
foreach ( $domains as $domain ) {
// The default text domain is handled by `load_default_textdomain()`.
if ( 'default' === $domain ) {
continue;
}
/*
* Unload current text domain but allow them to be reloaded
* after switching back or to another locale.
*/
unload_textdomain( $domain, true );
get_translations_for_domain( $domain );
}
}
/**
* Changes the site's locale to the given one.
*
* Loads the translations, changes the global `$wp_locale` object and updates
* all post type labels.
*
* @since 4.7.0
*
* @global WP_Locale $wp_locale WordPress date and time locale object.
* @global PHPMailer\PHPMailer\PHPMailer $phpmailer
*
* @param string $locale The locale to change to.
*/
private function change_locale( $locale ) {
global $wp_locale, $phpmailer;
$this->load_translations( $locale );
$wp_locale = new WP_Locale();
WP_Translation_Controller::get_instance()->set_locale( $locale );
if ( $phpmailer instanceof WP_PHPMailer ) {
$phpmailer->setLanguage();
}
/**
* Fires when the locale is switched to or restored.
*
* @since 4.7.0
*
* @param string $locale The new locale.
*/
do_action( 'change_locale', $locale );
}
}