给后台文章列表添加缩略图展示

在主题根目录下的 functions.php 文件<?下添加以下代码：

if ( !function_exists('fb_AddThumbColumn') && function_exists('add_theme_support') ) {
 // for post and page
 add_theme_support('post-thumbnails', array( 'post', 'page' ) );
 function fb_AddThumbColumn($cols) {
 $cols['thumbnail'] = __('Thumbnail');
 return $cols;
 }
 function fb_AddThumbValue($column_name, $post_id) {
 $width = (int) 35;
 $height = (int) 35;
 if ( 'thumbnail' == $column_name ) {
 // thumbnail of WP 2.9
 $thumbnail_id = get_post_meta( $post_id, '_thumbnail_id', true );
 // image from gallery
 $attachments = get_children( array('post_parent' => $post_id, 'post_type' => 'attachment', 'post_mime_type' => 'image') );
 if ($thumbnail_id)
 $thumb = wp_get_attachment_image( $thumbnail_id, array($width, $height), true );
 elseif ($attachments) {
 foreach ( $attachments as $attachment_id => $attachment ) {
 $thumb = wp_get_attachment_image( $attachment_id, array($width, $height), true );
 }
 }
 if ( isset($thumb) && $thumb ) {
 echo $thumb;
 } else {
 echo __('None');
 }
 }
 }
 // for posts
 add_filter( 'manage_posts_columns', 'fb_AddThumbColumn' );
 add_action( 'manage_posts_custom_column', 'fb_AddThumbValue', 10, 2 );
 // for pages
 add_filter( 'manage_pages_columns', 'fb_AddThumbColumn' );
 add_action( 'manage_pages_custom_column', 'fb_AddThumbValue', 10, 2 );
 }