WordPress后台文章列表添加复制文章按钮的方法

早些时候追格小编分享过一篇《WordPress主题：在网页复制文章时自动带上版权小尾巴》，今天分享WordPress后台文章列表添加一键复制文章的按钮。

当然也可以安装WordPress插件Post Duplicator来实现该功能，下面说说无需插件的方法。

        // 复制文章
        function zhuige_clone_post_as_draft() {
          global $wpdb;
          if (! ( isset( $_GET['post']) || isset( $_POST['post'])  || ( isset($_REQUEST['action']) && 'zhuige_clone_post_as_draft' == $_REQUEST['action'] ) ) ) {
            wp_die('No post to clone has been supplied!');
          }

          //  Nonce 验证
          if ( !isset( $_GET['clone_nonce'] ) || !wp_verify_nonce( $_GET['clone_nonce'], basename( __FILE__ ) ) )
          return;
    
          // 获取原文章ID
          $post_id = (isset($_GET['post']) ? absint( $_GET['post'] ) : absint( $_POST['post'] ) );     

          // 所有文章数据
          $post = get_post( $post_id );
    
          // 若不希望当前用户作为新文章作者，将下两行替换为$new_post_author = $post->post_author;
          $current_user = wp_get_current_user();
          $new_post_author = $current_user->ID;     

          // 如果发布数据存在，则创建发布克隆
          if (isset( $post ) && $post != null) {    

          // 创建新文章数组
            $args = array(
              'comment_status' => $post->comment_status,
              'ping_status'    => $post->ping_status,
              'post_author'    => $new_post_author,
              'post_content'   => $post->post_content,
              'post_excerpt'   => $post->post_excerpt,
              'post_name'      => $post->post_name,
              'post_parent'    => $post->post_parent,
              'post_password'  => $post->post_password,
              'post_status'    => 'draft',
              'post_title'     => $post->post_title,
              'post_type'      => $post->post_type,
              'to_ping'        => $post->to_ping,
              'menu_order'     => $post->menu_order
            );     

            // 通过wp_insert_post() 函数添加文章
            $new_post_id = wp_insert_post( $args );
     
            // 将新的文章设置为草稿
            $taxonomies = get_object_taxonomies($post->post_type); // 返回文章类型的分类数组，例如：array("category", "post_tag");
            foreach ($taxonomies as $taxonomy) {
              $post_terms = wp_get_object_terms($post_id, $taxonomy, array('fields' => 'slugs'));
              wp_set_object_terms($new_post_id, $post_terms, $taxonomy, false);
            }
     
            // 查询复制所有文章信息 post meta
            $post_meta_infos = $wpdb->get_results("SELECT meta_key, meta_value FROM $wpdb->postmeta WHERE post_id=$post_id");
            if (count($post_meta_infos)!=0) {
              $sql_query = "INSERT INTO $wpdb->postmeta (post_id, meta_key, meta_value) ";
              foreach ($post_meta_infos as $meta_info) {
                $meta_key = $meta_info->meta_key;
                if( $meta_key == '_wp_old_slug' ) continue;
                $meta_value = addslashes($meta_info->meta_value);
                $sql_query_sel[]= "SELECT $new_post_id, '$meta_key', '$meta_value'";
              }
              $sql_query.= implode(" UNION ALL ", $sql_query_sel);
              $wpdb->query($sql_query);
            }
            wp_redirect( admin_url( 'edit.php?post_type='.$post->post_type ) );
            exit;
          } else {
            wp_die('Post creation failed, could not find original post: ' . $post_id);
          }
        }
        add_action( 'admin_action_zhuige_clone_post_as_draft', 'zhuige_clone_post_as_draft' );

        // 复制文章并添加到列表
        function zhuige_clone_post_link( $actions, $post ) {
          if (current_user_can('edit_posts')) {
            $actions['clone'] = '<a href="' . wp_nonce_url('admin.php?action=zhuige_clone_post_as_draft&post=' . $post->ID, basename(__FILE__), 'clone_nonce' ) . '" title="Clone this '.$post->post_type.'" rel="permalink">复制</a>';
          }
          return $actions;
        }    
        add_filter( 'post_row_actions', 'zhuige_clone_post_link', 10, 2 );
        add_filter('page_row_actions', 'zhuige_clone_post_link', 10, 2);

我们在当前使用的WordPress模板 functions.php 中添加以上代码即可。