使用get_posts 要获取此类别中的所有帖子，请循环查看并更新每个帖子的帖子元。

<?php
//get_posts uses same parameters as WP_Query hence using \'category_name\'
$tut_posts = get_posts(array(\'category_name\'=>\'tution\', \'post_status\'=>\'publish\'));
$url = //some youtube video url here
if(!empty($tut_posts)){
    foreach($tut_posts as $tut_post){
        update_post_meta($tut_post->ID, \'video\', $url);
    }
}