下載服務器文件

 public void FileDownLoad()
        {
            string fileName = "201216157165144.txt";//客戶端保存的文件名

            string filePath = Server.MapPath("/File/201216157165144存儲過程分頁.txt");//路徑

            System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath);
            if (fileInfo.Exists == true)
            {
                const long ChunkSize = 102400;//100K 每次讀取文件，只讀取100K，這樣可以緩解服務器的壓力

                byte[] buffer = new byte[ChunkSize];

                Response.Clear();

                System.IO.FileStream iStream = System.IO.File.OpenRead(filePath);

                long dataLengthToRead = iStream.Length;//獲取下載的文件總大小

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

                Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName)); while (dataLengthToRead > 0 && Response.IsClientConnected)
                {
                    int lengthRead = iStream.Read(buffer, 0, Convert.ToInt32(ChunkSize));//讀取的大小

                    Response.OutputStream.Write(buffer, 0, lengthRead);

                    Response.Flush();

                    dataLengthToRead = dataLengthToRead - lengthRead;
                }

                Response.Close();
            }

        }