不久前，我在我的一个网站上添加了一个功能，可以将一组帖子从一种类型更改为另一种类型。我记不清确切的原因，但我已经把它挖了出来，并对它进行了一点更新，它已经过测试，并且工作正常。

将此功能放入functions.php 这样就可以在你博客的任何地方调用它。

/**
 * Change the type of a WP_Post object
 *
 * @param required array $posts         An array of post objects to update
 * @param required string $change_to    The post type to change the selected objects to
 * @param string $change_from           The post type to change the selected objects from (ignored if \'false\')
 */
function my_change_post_type($posts, $change_to, $change_from = false){

    /** Ensure that an array of objects has been passed */
    if(!is_array($posts))
        return new WP_Error(\'change_post_type\', __(\'<h4>Function \\\'my_change_post_type()\\\'</h4>The $posts array is empty, unable to proceed.\'));

    /** Ensure that $change_to is a valid post type */
    if(!post_type_exists($change_to))
        return new WP_Error(\'change_post_type\', __(sprintf(\'<h4>Function \\\'my_change_post_type()\\\'</h4>The value of the <b>$change_to</b> parameter (<b>%1$s</b>) is not a valid post type, unable to proceed.\', $change_to)));

    /** Loop through each object in the $posts array... */
    foreach($posts as $key => $post) :

        /** Ensure that this $post is actually a \'WP_Post\' object... */
        if(!is_a($post, \'WP_Post\')) : // It is not, so unset this $post and continue to the next (no need to update what hasn\'t changed)
            unset($posts[$key]);
            continue;
        endif;

        /** Check whether or not $change_from has been set... */
        if($change_from) :  // It has

            /** Ensure that $change_from is formatted as an array... */
            if(!array())    // It is not, so make it an array
                $change_from = (array)$change_from;

            /** Check if the post type needs to be changed... */
            if(in_array($post->post_type, $change_from)) :  // It does, so change it
                $post->post_type = $change_to;
            else :
                unset($posts[$key]);    // It does not, so unset this $post (no need to update what hasn\'t changed)
            endif;

        else :  // It has not, so change the post type
            $post->post_type = $change_to;
        endif;

    endforeach;

    /** Finally, update $posts (if there are any) */
    if(!empty($posts)) :
        wp_update_post($posts);
        return true;
    else:
        return false;
    endif;

}

如何使用要使用此函数，只需向其传递WP_Post 对象和要将其设置为的帖子类型。

正如我在对你的问题的评论中提到的，我建议使用你想要更改的对象的ID，首先只抓取那些帖子，如下所示-

$args = array(
    \'post__in\'  => array(12,58,79,105)
);
$posts = get_posts($args);
$result = my_change_post_type($posts, \'page\');

然而，如果你不想挑出某些对象，只想将所有帖子更改为页面，你可以抓取所有帖子-

$args = array(
    \'post_type\' => \'post\'
);
$posts = get_posts($args);
$result = my_change_post_type($posts, \'page\');

如果需要，您还必须选择从多个帖子类型更改为单个类型（例如，如果您决定不推荐几个自定义帖子类型，并希望将其中的所有对象设置为帖子）-

$posts = get_posts(array());
$result = my_change_post_type($posts, \'page\', array(\'cpt_1\', \'cpt_2\'));

错误处理另外，如果需要，您可以检查my_change_post_type() 函数并停止执行。

if(is_wp_error($result)) :
    wp_die($result);
endif;