WordPress自动保存文章里远程图片[代码+插件]

前言说明

在我们使用WordPress写文章时可能用不到这个功能，但对于搬站的站长还是挺有用，因为我们很多站长发布的文章基本上都不是自己写的，大多数都是复制粘贴别人的，因为是复制粘贴，这样链接是别人的，对于SEO也别不是很友好，也容易失效，如果我们手动处理，工作量也太大了，下面的代码我们能实现自动保存图片，并把第一张图设置为特色图像，使用起来更加方便。

教程方法

代码方式

1.大家可以把下面的代码复制到自己当前主题的“functions.php”文件里：

add_action('save_post', 'fetch_images');
add_action('publish_post', 'fetch_images');

function fetch_images( $post_ID )  
{	
	//Check to make sure function is not executed more than once on save
	if ( defined('DOING_AUTOSAVE') && DOING_AUTOSAVE ) 
	return;

	if ( !current_user_can('edit_post', $post_ID) ) 
	return;

	//Check if there is already a featured image; if there is, then quit.
	if ( '' != get_the_post_thumbnail() )
	return;

	remove_action('save_post', 'fetch_images');
        remove_action('publish_post', 'fetch_images');	
		
	$post = get_post($post_ID);   

	$first_image = '';
	
	if(preg_match_all('/<img.+src=[\'"]([^\'"]+)[\'"].*>/i', $post->post_content, $matches)){
		$first_image = $matches [1] [0];
	}

	if (strpos($first_image,$_SERVER['HTTP_HOST'])===false)
	{
			
		//Fetch and Store the Image	
		$get = wp_remote_get( $first_image );
		$type = wp_remote_retrieve_header( $get, 'content-type' );
		$mirror = wp_upload_bits(rawurldecode(basename( $first_image )), '', wp_remote_retrieve_body( $get ) );
	
		//Attachment options
		$attachment = array(
		'post_title'=> basename( $first_image ),
		'post_mime_type' => $type
		);
		
		// Add the image to your media library and set as featured image
		$attach_id = wp_insert_attachment( $attachment, $mirror['file'], $post_ID );
		$attach_data = wp_generate_attachment_metadata( $attach_id, $first_image );
		wp_update_attachment_metadata( $attach_id, $attach_data );
		set_post_thumbnail( $post_ID, $attach_id );
	
		$updated = str_replace($first_image, $mirror['url'], $post->post_content);
	    
	    //Replace the image in the post
	    wp_update_post(array('ID' => $post_ID, 'post_content' => $updated));
	
	    // re-hook this function
	    add_action('save_post', 'fetch_images');
      add_action('publish_post', 'fetch_images');				
	}
}

注意：本代码不适合那种直接用采集插件或火车头类采集远程图像入库的！