Question

i am using WCF to upload and download a file. and i am using the following the for download.

try
        {
            MyService.IWITSService clientDownload = new WITSServiceClient();
            MyService.DownloadRequest requestData = new DownloadRequest();
            MyService.RemoteFileInfo fileInfo = new RemoteFileInfo();
            requestData.ItemID = Convert.ToInt32(Request.QueryString["id"]);

            fileInfo = clientDownload.DownloadFile(requestData);

            Response.BufferOutput = false;   // to prevent buffering 
            byte[] buffer = new byte[6500000];
            int bytesRead = 0;

            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.ClearHeaders();
            HttpContext.Current.Response.ContentType = fileInfo.FileExt;
            HttpContext.Current.Response.AddHeader("Content-Disposition","attachment; filename=" + fileInfo.FileName);

            bytesRead = fileInfo.FileByteStream.Read(buffer, 0, buffer.Length);

            while (bytesRead > 0)
            {
                // Verify that the client is connected.
                if (Response.IsClientConnected)
                {

                    Response.OutputStream.Write(buffer, 0, bytesRead);
                    // Flush the data to the HTML output.
                    Response.Flush();

                    buffer = new byte[6500000];
                    bytesRead = fileInfo.FileByteStream.Read(buffer, 0, buffer.Length);

                }
                else
                {
                    bytesRead = -1;
                }
            }
        }
        catch (Exception ex)
        {
            // Trap the error, if any.
            System.Web.HttpContext.Current.Response.Write("Error : " + ex.Message);
        }
        finally
        {
            Response.Flush();
            Response.Close();
            Response.End();
            System.Web.HttpContext.Current.Response.Close();
        }

file is downloaded but file data is not display. file size is same as an actual
size. can any one help me where i have to change..
Thanks in advance..

Answer 1

You don’t want to call neither Response.Close() nor System.Web.HttpContext.Current.Response.Close(). It interrupts the connection to the client.

The documentation of HttpResponse.Close Method says:

This method terminates the connection to the client in an abrupt
manner and is not intended for normal HTTP request processing. The
method sends a reset packet to the client, which can cause response
data that is buffered on the server, the client, or somewhere in
between to be dropped.

You might use this method in response to an attack by a malicious HTTP
client. However, typically you should call CompleteRequest instead if
you want to jump ahead to the EndRequest event and send a response to
the client.

So reduce the finally code to:

finally
{
    Response.Flush();
    Response.End();
}