Download/Stream file from URL – asp.net

You could use HttpWebRequest to get the file and stream it back to the client. This allows you to get the file with a url. An example of this that I found ( but can’t remember where to give credit ) is

    //Create a stream for the file
    Stream stream = null;

    //This controls how many bytes to read at a time and send to the client
    int bytesToRead = 10000;

    // Buffer to read bytes in chunk size specified above
    byte[] buffer = new Byte[bytesToRead];

    // The number of bytes read
    try
    {
      //Create a WebRequest to get the file
      HttpWebRequest fileReq = (HttpWebRequest) HttpWebRequest.Create(url);

      //Create a response for this request
      HttpWebResponse fileResp = (HttpWebResponse) fileReq.GetResponse();

      if (fileReq.ContentLength > 0)
        fileResp.ContentLength = fileReq.ContentLength;

        //Get the Stream returned from the response
        stream = fileResp.GetResponseStream();

        // prepare the response to the client. resp is the client Response
        var resp = HttpContext.Current.Response;

        //Indicate the type of data being sent
        resp.ContentType = MediaTypeNames.Application.Octet;
    
        //Name the file 
        resp.AddHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
        resp.AddHeader("Content-Length", fileResp.ContentLength.ToString());
    
        int length;
        do
        {
            // Verify that the client is connected.
            if (resp.IsClientConnected)
            {
                // Read data into the buffer.
                length = stream.Read(buffer, 0, bytesToRead);

                // and write it out to the response's output stream
                resp.OutputStream.Write(buffer, 0, length);

                // Flush the data
                resp.Flush();

                //Clear the buffer
                buffer = new Byte[bytesToRead];
            }
            else
            {
                // cancel the download if client has disconnected
                length = -1;
            }
        } while (length > 0); //Repeat until no data is read
    }
    finally
    {
        if (stream != null)
        {
            //Close the input stream
            stream.Close();
        }
    }

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