好的，这只是一个如何存档的示例。。

首先将上载目录更改为当前用户用户名。例如上传/管理

function wpse_16722_type_upload_dir( $args ) {
    // Get current user data
    $current_user = wp_get_current_user();

    // Make upload dir to current username
    $newdir = \'/\' . $current_user->user_login;

    $args[\'path\']    = str_replace( $args[\'subdir\'], \'\', $args[\'path\'] ); //remove default subdir
    $args[\'url\']     = str_replace( $args[\'subdir\'], \'\', $args[\'url\'] );      
    $args[\'subdir\']  = $newdir;
    $args[\'path\']   .= $newdir; 
    $args[\'url\']    .= $newdir; 

    return $args;
}
add_filter( \'upload_dir\', \'wpse_16722_type_upload_dir\' );

然后我们需要一个函数来检查当前用户上传的大小。我发现一个函数recurse_dirsize 在内部ms-functions.php 以字节为单位计算目录。

/**
 * Get the size of a directory recursively.
 *
 * Used by get_dirsize() to get a directory\'s size when it contains
 * other directories.
 *
 * @since MU
 *
 * @param string $directory
 * @return int
 */
function recurse_dirsize( $directory ) {
    $size = 0;

    $directory = untrailingslashit( $directory );

    if ( !file_exists($directory) || !is_dir( $directory ) || !is_readable( $directory ) )
        return false;

    if ($handle = opendir($directory)) {
        while(($file = readdir($handle)) !== false) {
            $path = $directory.\'/\'.$file;
            if ($file != \'.\' && $file != \'..\') {
                if (is_file($path)) {
                    $size += filesize($path);
                } elseif (is_dir($path)) {
                    $handlesize = recurse_dirsize($path);
                    if ($handlesize > 0)
                        $size += $handlesize;
                }
            }
        }
        closedir($handle);
    }
    return $size;
}

然后，我们需要检查当前用户上传的内容是否大于x，如果是，请禁用media_buttons

function wpse_16722_user_upload_size() {
    // Get current user data
    $current_user = wp_get_current_user();

    // Array of key => value pairs
    $uploads = wp_upload_dir(); 

    $dir = $uploads[\'basedir\'] . \'/\' .  $current_user->user_login;

    if( file_exists( $dir ) && is_dir( $dir ) ) {
        $size = recurse_dirsize( $dir ) / 1024 / 1024;

        // Convert bytes to human readable format
        $new_size = round( $size / 1024 * 1024, 2 );

        // If current users upload dir is
        // Bigger than 20 MB disable
        // Upload buttton
        if( $new_size  >= 20 ) {
            remove_action( \'media_buttons\', \'media_buttons\' );
        }


    }
}
add_action(\'admin_head\', \'wpse_16722_user_upload_size\');

您还希望控制多个用户和不同的大小。我建议您添加一个设置页面，用以保存用户可用大小update_user_meta($user_id, \'size_limit\', $value ); 了解更多信息here

当您将尺寸添加到users_meta 您可以在函数中更改大小wpse_16722_user_upload_size “20”至以下尺寸get_user_meta( $user_id, \'size_limit\');

// this function disable media buttons
function removemediabuttons()
{
   remove_action( \'media_buttons\', \'media_buttons\' );
}

// this function check the total size of all attachments by user. 
//But it doesnt count sizes of thumbnails. 
// $limitBytes -- maximum size in bytes
function checkMidiaSizeByUser($userId, $limitBytes) 
{
    // get all attachments of $userId
    $attachements = query_posts(
      array(
        \'post_type\' => \'attachment\',
        \'author\' => $userId
      )
    );
    // count size
    $size = 0;
    foreach($attachements as $attachment){
      $size += filesize( get_attached_file( $attachment->ID ) );
    }
    // check limit
    if ( $size >= $limitBytes ) {
      add_action(\'admin_head\',\'removemediabuttons\');
    }
}

/* **************************************** */

// Set our limit to 20Mb
$limit = 20*1024*1024; 

// get current user
global $current_user;
get_currentuserinfo(); 

//check limit and disable media buttons if user met limit
checkMidiaSizeByUser($current_user->ID, $limit);

我不会在实际工作中测试此代码，但它应该可以工作。