WordPress默认的上传文件的目录是/wp-content/uploads，而且文件是以年月的形式组织的，虽然我们可以去掉按照年月组织的选项，或者更改存储路径，但这个设置会应用到全局，不能按照特定条件选择特定目录存储文件。

 

有时候将不同类型的文件分门别类存储，似乎比年月目录更有意义。例如幻灯片应该存储在slides目录下，下载文件应该存储在downloads文件夹下。就说幻灯片slideshow，我比较喜欢用自定义文章类型（Custom Post Type）实现，有些幻灯片脚本比较个性，不支持绝对路径，必须用相对路径，然后用base参数设置相对于哪个文件夹，这样幻灯片必须存储在某个特定的文件夹中，年月形式显然不满足要求。所以，我们需要条件化的设置上传目录。

为Custom Post Type设置上传目录

假设我要将所有在幻灯片类型的文章中上传的文件存储到/wp-content/uploads/slides文件夹中，将下面的代码放到主题的functions.php中即可


function custom_upload_directory( $uploads ) {        
                  $id = $_REQUEST[         'post_id'         ];        
                  $parent = get_post( $id )->post_parent;        
                  if         (          "post-type"          == get_post_type( $id ) ||          "post-type"          == get_post_type( $parent ) ) {        
                  $subdir =          'slides'         ;        
                  $uploads[         'subdir'         ] = $subdir;        
                  $uploads[         'path'         ] = $uploads[         'basedir'         ].DIRECTORY_SEPARATOR.$subdir;        
                  $uploads[         'url'         ] = $uploads[         'baseurl'         ].         '/'         .$subdir;        
                  }        
                  return          $uploads;        
         }        
         add_filter(          'upload_dir'         ,          'custom_upload_directory'          );



将post-type替换成自己的自定义文章类型名称，将你要创建的子目录赋值给$subdir。

将文件保存到插件目录

下面的代码要用在插件中，文件会保存到插件目录下的uploads文件夹下。



/**        
                  * Change Upload Directory for Custom Post-Type        
                  *        
                  * This will change the upload directory for a custom post-type. Attachments will        
                  * now be uploaded to an "uploads" directory within the folder of your plugin. Make        
                  * sure you swap out "post-type" in the if-statement with the appropriate value...        
                  */        
         function custom_upload_directory( $args ) {        
                  $id = $_REQUEST[         'post_id'         ];        
                  $parent = get_post( $id )->post_parent;        
                  // Check the post-type of the current post        
                  if         (          "post-type"          == get_post_type( $id ) ||          "post-type"          == get_post_type( $parent ) ) {        
                  $args[         'path'         ] = plugin_dir_path(__FILE__) .          "uploads"         ;        
                  $args[         'url'         ]  = plugin_dir_url(__FILE__) .          "uploads"         ;        
                  $args[         'basedir'         ] = plugin_dir_path(__FILE__) .          "uploads"         ;        
                  $args[         'baseurl'         ] = plugin_dir_url(__FILE__) .          "uploads"         ;        
                  }        
                  return          $args;        
         }        
         add_filter(          'upload_dir'         ,          'custom_upload_directory'          );



如果要以年月形式保存，修改一下代码即可


$args         [         'path'         ] = plugin_dir_path(         __FILE__         ) .          "uploads"          .          $args         [         'subdir'         ];        
         $args         [         'url'         ]  = plugin_dir_url(         __FILE__         ) .          "uploads"          .          $args         [         'subdir'         ];



这段代码来自 http://wordpress.stackexchange.com/questions/35657/how-to-add-more-upload-directories/

为后台管理页面设定upload_dir

用wp_editor在后台管理页面（比如用add_menu_page创建的页面）创建一个媒体上传功能，希望所有从该页面上传的文件都保存到wp-content/uploads/myfolder目录下。

由 于ajax上传是直接调用wp-admin/async_upload.php文件，只能通过post_id获取post信息，而后台管理页面并非 post，所以判断什么时候应该更改upload_dir有些麻烦。此时，可以用采用判断页面referer的方法,用wp_get_referer() 函数获取引荐url，如果正好与我们的option page url想等，就更该目录。



function          custom_upload_directory(          $uploads          ) {        
                  if         ( wp_get_referer() ==          'http://domain.com/wp-admin/admin.php?page=myoptionpage'         ){        
                  $subdir          =          'myfolder'         ;        
                  $uploads         [         'subdir'         ] =          $subdir         ;        
                  $uploads         [         'path'         ] =          $uploads         [         'basedir'         ].DIRECTORY_SEPARATOR.         $subdir         ;        
                  $uploads         [         'url'         ] =          $uploads         [         'baseurl'         ].         '/'         .         $subdir         ;        
                  }        
                  return          $uploads         ;        
         }        
         add_filter(          'upload_dir'         ,          'custom_upload_directory'          );



参考信息

filter:upload_dir是在wp_upload_dir()函数中调用的

$upload_dir = wp_upload_dir();
$upload_dir now contains something like the following (if successful)
Array (
[path] => C:pathtowordpresswp-contentuploads20105
[url] => http://example.com/wp-content/uploads/2010/05
[subdir] => /2010/05
[basedir] => C:pathtowordpresswp-contentuploads
[baseurl] => http://example.com/wp-content/uploads
[error] =>
)