MVC下载文件方式

public FileStreamResult DownFile(string filePath, string fileName)  
        {  
            string absoluFilePath = Server.MapPath(System.Configuration.ConfigurationManager.AppSettings["AttachmentPath"] + filePath);  
            return File(new FileStream(absoluFilePath, FileMode.Open), "application/octet-stream", Server.UrlEncode(fileName));  
        }  

public ActionResult DownFile(string filePath, string fileName)  
        {  
            filePath = Server.MapPath(System.Configuration.ConfigurationManager.AppSettings["AttachmentPath"] + filePath);  
            FileStream fs = new FileStream(filePath, FileMode.Open);  
            byte[] bytes = new byte[(int)fs.Length];  
            fs.Read(bytes, 0, bytes.Length);  
            fs.Close();  
            Response.Charset = "UTF-8";  
            Response.ContentEncoding = System.Text.Encoding.GetEncoding("UTF-8");  
            Response.ContentType = "application/octet-stream";  
  
            Response.AddHeader("Content-Disposition", "attachment; filename=" + Server.UrlEncode(fileName));  
            Response.BinaryWrite(bytes);  
            Response.Flush();  
            Response.End();  
            return new EmptyResult();  
  
        }