/// <summary>
 /// 添加附件到数据库
 /// </summary>
 /// <param name="model"></param>
 /// <returns></returns>
 public int AddFile(Attachment model)
 {
     var file = db.Attachments.Add(model);
     db.SaveChanges();
     int row = 0;
     if (file != null)
     {
         row = file.Id;
     }
     return row;
 }
        /// <summary>
        /// 上传文件,返回存储文件的Id
        /// </summary>
        /// <returns></returns>
        public JsonResult UploadFile()
        {
            string result = "";
            int row = 0;
            foreach (string upload in Request.Files)
            {
                if (!HasFiles.HasFile(Request.Files[upload]))
                {
                    continue;
                }
                string miniType = Request.Files[upload].ContentType;
                string fileType = Path.GetExtension(Request.Files[upload].FileName);
                Stream fileStream = Request.Files[upload].InputStream;
                string oldFilename = Path.GetFileName(Request.Files[upload].FileName);
                DateTime nowTime = DateTime.Now;
                Random rd = new Random();
                string newFileName = nowTime.Year.ToString() + nowTime.Month.ToString() + nowTime.Day.ToString() + nowTime.Hour.ToString()
                    + nowTime.Minute.ToString() + nowTime.Second.ToString() + rd.Next(1000, 1000000) + ".jpg";
                string rootPath = HttpContext.Server.MapPath("../../UpLoadFile/");
                string temp = @"../../UpLoadFile/";
                int size = Request.Files[upload].ContentLength;
                if (!Directory.Exists(rootPath))
                {
                    Directory.CreateDirectory(rootPath);
                }
                Request.Files[upload].SaveAs(rootPath + newFileName);

                var file = new Attachment()
                {
                    FileType = fileType,
                    FileSzie = size,
                    OldFileName = newFileName,
                    NewFileName = oldFilename,
                    FilePath = temp,
                    AddTime = nowTime
                };

                row = repository.AddFile(file);
                result += row + ",";
            }

            return Json(row);
        }