[实战]MVC5+EF6+MySql企业网盘实战(15)——逻辑重构2

        /// <summary>
        /// 文件下载
        /// </summary>
        /// <param name="fileId"></param>
        public void DownLoadFile(string fileId)
        {
            UserInfo userInfo = Session["user"] as UserInfo;
            if (userInfo == null)
            {
                RedirectToAction("Login", "UserInfo");
                return;
            }
            if (string.IsNullOrEmpty(fileId))
            {
                throw new ArgumentNullException("fileId is errror");
            }
            int id = Convert.ToInt32(fileId);
            var findFile = _myFileServiceRepository.Find(x => x.Id == id);
            if (findFile == null)
            {
                AlertMsg("文件不存在", "");
                return;
            }
            string filePath = Path.Combine(Server.MapPath("~/NetDisk/"), findFile.FileMd5 + findFile.FileExt);
            //以字符流的形式下载文件
            FileStream fs = new FileStream(filePath, FileMode.Open);
            byte[] bytes = new byte[(int)fs.Length];
            fs.Read(bytes, 0, bytes.Length);
            fs.Close();
            Response.ContentType = "application/octet-stream";
            //通知浏览器下载文件而不是打开
            Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(findFile.FileName, System.Text.Encoding.UTF8));
            Response.BinaryWrite(bytes);
            Response.Flush();
            Response.End();
        }