我正在WPMS上使用一个新的博客（3.0.1，不可更新）来聚合来自同一安装上几个博客的帖子（及其特色图片），由于防火墙的限制，我必须通过编程而不是通过预先制作的插件来完成。我试过几种方法this method 是最有希望的。以下是我做的：

switch_to_blog(oldblognumber);
$zargs  = array( \'numberposts\' => 1, \'category_name\' => \'featured\');
$zlastpost = get_posts( $zargs );
foreach($zlastpost as $post) : setup_postdata($post);
    $extrapost = array();
    $extrapost[\'post_title\'] = get_the_title();
    $extrapost[\'post_content\'] = get_the_content();
    $extrapost[\'comment_status\'] = \'closed\';
    $extrapost[\'post_status\'] = \'publish\';
    $extrapost[\'post_date\'] = get_the_date( $d = \'Y-m-d H:i:s\');
    $extrapost[\'post_category\'] = array(80);
    $upload_dir = wp_upload_dir();
    $oldid = get_the_ID();
    $image_url = wp_get_attachment_url(get_post_thumbnail_id($oldid));
    $image_data = file_get_contents($image_url);
    $filename = basename($image_url);
    switch_to_blog(newblognumber);          
        $file = $upload_dir[\'path\'] . \'/\' . $filename; //removed the conditional cuz it was giving me trouble
        file_put_contents($file, $image_data);
        $post_id = wp_insert_post($extrapost);
        $wp_filetype = wp_check_filetype($filename, null );
        $attachment = array(
            \'post_mime_type\' => $wp_filetype[\'type\'],
            \'post_title\' => sanitize_file_name($filename),
            \'post_content\' => \'\',
            \'post_status\' => \'inherit\',
        );                  
        $attach_id = wp_insert_attachment( $attachment, $file, $post_id );
        require_once(ABSPATH . \'wp-admin/includes/image.php\');
        $attach_data = wp_generate_attachment_metadata( $attach_id, $file );
        wp_update_attachment_metadata( $attach_id, $attach_data );
        set_post_thumbnail( $post_id, $attach_id );                       
    restore_current_blog();
    wp_reset_postdata();
endforeach;
restore_current_blog();

同样，在我请求\\u post\\u缩略图的循环中，我得到了一个损坏的图像，其src为http://myblogs.com/newblog/files//internet/http/wp-content/blogs.dir/oldblognumber/files/year/month/filename-200x100.jpg

值得一提的是，由于我使用的是WP的pre-set\\u post\\u缩略图版本，所以我只需在我的newblog函数中手动定义该函数。php：

function set_post_thumbnail( $post, $thumbnail_id ) {
$post = get_post( $post );
$thumbnail_id = absint( $thumbnail_id );
if ( $post && $thumbnail_id && get_post( $thumbnail_id ) ) {
   $thumbnail_html = wp_get_attachment_image( $thumbnail_id, \'thumbnail\' );
   if ( ! empty( $thumbnail_html ) ) {
       update_post_meta( $post->ID, \'_thumbnail_id\', $thumbnail_id );
       return true;
   }
}
return false;
}

我还尝试了另一种方法来设置插入帖子的帖子缩略图，但这只是调用oldblog的上载目录中的原始文件，这是不够的，因为我想为新博客的媒体库生成新的图像大小，我不想遍历并将其添加到每个原始oldblog中。这是一次尝试：

switch_to_blog(oldblognumber);
$zargs  = array( \'numberposts\' => 1, \'category_name\' => \'featured\');
$zlastpost = get_posts( $zargs );
foreach($zlastpost as $post) : setup_postdata($post);
    $extrapost = array();
    $extrapost[\'post_title\'] = get_the_title();
    $extrapost[\'post_content\'] = get_the_content();
    $extrapost[\'comment_status\'] = \'closed\';
    $extrapost[\'post_status\'] = \'publish\';
    $extrapost[\'post_date\'] = get_the_date( $d = \'Y-m-d H:i:s\');
    $extrapost[\'post_category\'] = array(80);
    $oldid = get_the_ID();
    $thumbo = get_the_post_thumbnail($oldid);
    $filename = wp_get_attachment_url( get_post_thumbnail_id($post->ID) );
    switch_to_blog(68);
        $post_id = wp_insert_post($extrapost);
        $wp_filetype = wp_check_filetype(basename($filename), null );
            $wp_upload_dir = wp_upload_dir();
            $attachment = array(
                \'guid\' => _wp_relative_upload_path( $filename ), 
                \'post_mime_type\' => $wp_filetype[\'type\'],
                \'post_title\' => preg_replace(\'/\\.[^.]+$/\', \'\', basename($filename)),
                \'post_content\' => \'\',
                \'post_status\' => \'inherit\'
            );
            $attach_id = wp_insert_attachment( $attachment, false, $post_id );
            require_once(ABSPATH . \'wp-admin/includes/image.php\');
            $attach_data = wp_generate_attachment_metadata( $attach_id, $filename );
            update_post_meta( $post->ID, \'_thumbnail_id\', $attachment_id );
            wp_update_attachment_metadata( $attach_id, $attach_data );
            set_post_thumbnail( $post_id, $attach_id);        
        restore_current_blog();
        wp_reset_postdata();
    endforeach;
restore_current_blog();