'.$city.''; } } $continentsHtml = ''; $continents = array_keys($continents); foreach ($continents as $continent) { $continentsHtml .= ''; } // Timezone selection form $timezoneForm = 'Continent:'; $timezoneForm .= ''; $timezoneForm .= $continentsHtml.''; $timezoneForm .= '    City:'; $timezoneForm .= ''.$cities[$pcontinent].'
'; // Javascript handler - updates the city list when the user selects a continent $timezoneJs = ''; return array($timezoneForm, $timezoneJs); } /** * Tells if a continent/city pair form a valid timezone * * Note: 'UTC/UTC' is mapped to 'UTC' * * @param string $continent the timezone continent * @param string $city the timezone city * * @return bool whether continent/city is a valid timezone */ function isTimeZoneValid($continent, $city) { return in_array( $continent.'/'.$city, timezone_identifiers_list() ); }