你的想法是对的。如果您获得一个地区内的国家/地区ID数组，则可以将该数组传递给元查询进行比较：

$country_ids = array(1,2,3); // this would be the result from fetching countries associated with a region.
$args = array(
    \'posts_per_page\' => -1,
    \'meta_query\' => array(
        array(
            \'key\' => \'country\',
            \'value\' => $country_ids,
            \'compare\' => \'IN\'
        )
    )
);
$query = new WP_Query( $args );