ASP.NET MVC 以Stream 下载文件

 1.0以Stream 下载文件

 

            nl.fileid = Int32.Parse(id);  //服务器上对应的id

            Stream stream = Lawsuit.DownLoad(nl);//服务器上的Stream 数据



            Response.Buffer = false;

            Response.AddHeader("Connection", "Keep-Alive");

            Response.ContentType = "application/octet-stream";

            Response.AddHeader("Content-Disposition", "attachment;filename=" + url); // 此处文件名如果是中文在浏览器默认是筹码,应该加HttpUtility.UrlEncode(filename)   url：为下载文件的服务器地址和名称



            while (true)    //如果文件大于缓冲区，通过while循环多次加载文件 

            {

                //开辟缓冲区空间   

                byte[] buffer = new byte[1024];  //读取文件的数据   

                int leng = stream.Read(buffer, 0, 1024);

                if (leng == 0)             //到文件尾，结束   

                    break;

                if (leng == 1024)            //读出的文件数据长度等于缓冲区长度，直接将缓冲区数据写入  

                    Response.BinaryWrite(buffer);           //向客户端发送数据流 

                else

                {

                    //读出文件数据比缓冲区小，重新定义缓冲区大小，只用于读取文件的最后一个数据块  

                    byte[] b = new byte[leng]; for (int i = 0; i < leng; i++)

                        b[i] = buffer[i];

                    Response.BinaryWrite(b);

                }

            }

            stream.Close();//关闭下载文件  

            Response.End();//结束文件下载 

 1.1根据流创建pdf

 1         /// <summary>

 2         /// 根据流创建pdf

 3         /// </summary>

 4         /// <param name="_Stream"></param>

 5         /// <returns></returns>

 6         public string CreateCasePDF(Stream _Stream)

 7         {

 8             string pdfUrl = Server.MapPath("../Content/FilePdf");//pdf保存地址

 9             if (Directory.Exists(pdfUrl) == false)//如果不存在就创建PDFFile文件夹

10             {

11                 Directory.CreateDirectory(pdfUrl);

12             }

13             DocClient proxy = new DocClient();

14             try

15             {

16                 string guid = Guid.NewGuid().ToString();

17                 FileInfo file = new FileInfo(pdfUrl + guid + ".pdf");

18                 Stream write = file.OpenWrite();

19                 write.Position = long.Parse("0");

20                 byte[] buf = new byte[1024 * 2048];

21                 int size = -1;

22                 long sum = long.Parse("0");

23                 while ((size = _Stream.Read(buf, 0, buf.Length)) > 0)

24                 {

25                     write.Write(buf, 0, size);

26                     sum += size;

27                 }

28                 write.Close();

29                 _Stream.Close();

30                 return guid;

31             }

32             catch (Exception)

33             {

34                 return null;

35             }

36         }

 1.2根据流生成MD5

        /// <summary>

        /// 获取文件的MD5值

        /// </summary>

        /// <param name="stream"></param>

        /// <returns></returns>

        public static string GetMD5HashFromStream(Stream stream)

        {

            try

            {

                System.Security.Cryptography.MD5CryptoServiceProvider md5 = new System.Security.Cryptography.MD5CryptoServiceProvider();

                byte[] data = md5.ComputeHash(stream);

                StringBuilder sBuilder = new StringBuilder();

                for (int i = 0; i < data.Length; i++)

                {

                    sBuilder.Append(data[i].ToString("x2"));

                }

                return sBuilder.ToString().ToUpper();

            }

            catch (Exception ex)

            {

                throw new Exception("GetMD5HashFromFile() fail,error:" + ex.Message);

            }

        }

1.3删除指定目录下的文件，并再次创建

                string path = Server.MapPath("../Content/FilePdf");// 删除指定文件下的文件夹及其文件

                Directory.Delete(path, true);

                Directory.CreateDirectory(path);

 

 

 

 

来源地址：http://www.cnblogs.com/chaoa/archive/2012/03/09/2386106.html