ASP.Net下载大文件的实现方法

                // Total bytes to read.
                dataToRead = iStream.Length;

                Response.Clear();
                Response.ClearHeaders();
                Response.ClearContent();
                Response.ContentType = "text/plain"; // Set the file type
                Response.AddHeader("Content-Length", dataToRead.ToString());
                Response.AddHeader("Content-Disposition", "attachment; filename=" + filename);

                // Read the bytes.
                while (dataToRead > 0)
                {
                    // Verify that the client is connected.
                    if (Response.IsClientConnected)
                    {
                        // Read the data in buffer.
                        length = iStream.Read(buffer, 0, 10000);

                        // Write the data to the current output stream.
                        Response.OutputStream.Write(buffer, 0, length);

                        // Flush the data to the HTML output.
                        Response.Flush();

                        buffer = new Byte[10000];