rest_get_date_with_gmt

rest_get_date_with_gmt：该函数用于检索GMT时区的日期字符串。它接受一个单一的参数，一个日期字符串，并返回在GMT时区的同一日期。它在REST API中用于格式化日期字符串。

将一个日期解析为本地和UTC的等价物，以MySQL日期时间格式。

function rest_get_date_with_gmt( $date, $is_utc = false ) {
	/*
	 * Whether or not the original date actually has a timezone string
	 * changes the way we need to do timezone conversion.
	 * Store this info before parsing the date, and use it later.
	 */
	$has_timezone = preg_match( '#(Z|[+-]d{2}(:d{2})?)$#', $date );

	$date = rest_parse_date( $date );

	if ( empty( $date ) ) {
		return null;
	}

	/*
	 * At this point $date could either be a local date (if we were passed
	 * a *local* date without a timezone offset) or a UTC date (otherwise).
	 * Timezone conversion needs to be handled differently between these two cases.
	 */
	if ( ! $is_utc && ! $has_timezone ) {
		$local = gmdate( 'Y-m-d H:i:s', $date );
		$utc   = get_gmt_from_date( $local );
	} else {
		$utc   = gmdate( 'Y-m-d H:i:s', $date );
		$local = get_date_from_gmt( $utc );
	}

	return array( $local, $utc );
}