/// <summary>
        /// 下载指定路径的文件。
        /// </summary>
        /// <param name="path">指定要下载的文件的相对路径或绝对路径(绝对路径以/斜杠打头)。</param>
        public HttpResponseMessage Get(string path)
        {
            if (string.IsNullOrEmpty(path))
            {
                throw new HttpResponseException(HttpStatusCode.BadRequest);
            }

            return(_accessor.Read(path));
        }
        public HttpResponseMessage Download(string id)
        {
            var file = base.Get(id) as File;

            if (file == null || string.IsNullOrWhiteSpace(file.Path))
            {
                return(null);
            }

            var response = _accessor.Read(file.Path);

            if (response != null && response.Content != null && !string.IsNullOrWhiteSpace(file.Type))
            {
                response.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue(file.Type);
            }

            return(response);
        }