处理通过<input type="file">的Post 请求

  [HttpPost]
        public ActionResult Cal()
        {
            string ExcelName = System.DateTime.Now.ToString("yyyyMMddHHmmss");//表名yyyyMMddHHmmss 
            DataSet dsCal = new DataSet();
            if (Request.Files.Count != 0)
            {
                HttpPostedFileBase fb = Request.Files[0];
                // Stream sr = Request.Files["fileName"].InputStream; //获取到这个文件流
                string fileName = fb.FileName;  //获取到文件名  xx.xls
                string extenSion = Path.GetExtension(fileName);  //文件后缀 .xls

                if (extenSion.Equals(".xls") || extenSion.Equals(".xlsx"))
                {
                    //一：上传服务器
                    fb.SaveAs(Server.MapPath("~/App_Data/Excel/Model.xls"));
                    //二：将Excel表格转换为DadaSet数据集
                    dsCal = GetDataSet(fb.FileName);
                    //将五张基本表存入数据库中  获取年月
                    string year = Request.Form["selYear"].ToString();
                    string month = Request.Form["selMon"].ToString();
                    FillDataToDB(year, month, dsCal);
                }
                else
                {
                    //提示文件输入格式不正确
                }
            }
            return View("Index");
        }