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Writing data to Response, but keeping the page active

I'm trying to have a user click a button on a web page to download a CSV file, but I'm having problems sending the correct data to the user. In addition, once the file has been downloaded, I'd like the page to remain "active" i.e. the page can continue to trigger events to the server, such as clicking the Download button again.
This is the code I'm currently using, pieced together from various SO questions:
var sb = new StringBuilder();
string fileName = "data.csv";
// Build CSV file...
HttpContext.Current.Response.Clear();
HttpContext.Current.Response.ClearHeaders();
HttpContext.Current.Response.ClearContent();
HttpContext.Current.Response.AddHeader("content-disposition", string.Format("filename={0}", fileName));
HttpContext.Current.Response.ContentType = "text/csv";
HttpContext.Current.Response.Write(sb.ToString());
HttpContext.Current.Response.Flush();
HttpContext.Current.Response.End();
This works so far as presenting the user with an option to open or download the file, but the file also contains the entire markup of the aspx file after the requested data, and the page is left completely inactive.
I'm guessing the problem is with the last two lines of the above code. I've tried using ApplicationInstance.CompleteRequest instead of Response.End, but this doesn't seem to change the outcome. The page is still inactive and the file still has the markup at the end. Can anyone help?
In case it makes any difference in the behaviour of Response, the page is an WebPartPage in SharePoint 2010.

Set the line
HttpContext.Current.Response.AddHeader("content-disposition", "filename={0}", fileName));
to
HttpContext.Current.Response.AppendHeader("content-disposition", String.Format("attachment;filename={0}", fileName));
And set the following property on your button
downloadButton.OnClientClick = "_spFormOnSubmitCalled = false;";
_spFormOnSubmitCalled is a javascript variable that SharePoint uses to stop multiple form submits and it is being set to true when you click the download button.

try this
HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
HttpContext.Current.Response.ContentType = "application/CSV";

display *doc,*xls,*pdf in browser window instead

i want to display *doc,*xls,*pdf in browser window instead of their respected application. i have tried following code, but no luck it prompt me dialog for save/open instead of displaying in browser
//Set the appropriate ContentType.
Response.ContentType = "Application/msword";
//Get the physical path to the file.
string FilePath = MapPath("wordfile.doc");
//Write the file directly to the HTTP content output stream.
Response.AppendHeader("Content-Disposition", "inline;filename=" + "wordfile.doc");
Response.WriteFile(FilePath);
Response.End();
please help
thanks

for any of these proprietary formats you need browser plugins/extensions or ActiveX for IE
Am not sure if its available for office formats.
For PDF setting the content type to "application/pdf" and Content-Disposition to inline should work.

Chrome PDF Viewer "Save To Disk" feature - is it possible to control saved filename extension?

In an ASP.NET 2.0 application, using Google Chrome 13 on Windows.
My app dynamically generates a PDF report when the user browses to a particular aspx page. For the most part, things work fine on various browsers.
However, on Chrome, when Chrome's PDF viewer is being used, the following can happen :
- the user presses the floating diskette icon on the bottom right hand side of the viewer to save the PDF document. The file is saved with the aspx page's name. e.g. Report.aspx .
If I open that downloaded aspx file in Adobe Reader, it opens up ok as a PDF document. But is there a way to get chrome to default the name of the file to save to have a ".PDF" extension ?
EDIT :
The code for the report generation page looks something like this :
protected void Page_Load(object sender, EventArgs e)
{
Response.Clear();
Response.ContentType = "application/pdf";
byte[] data = GenerateReportHere(); // dynamically generate PDF report
Response.AddHeader("Content-Length", data.Length.ToString());
Response.BinaryWrite(data);
Response.Flush();
Response.End();
}
Note that I don't want to use a "Content-Disposition" header like :
Response.AddHeader("Content-Disposition", "attachment; filename=Report.pdf");
because that causes the browser to ask the user if they want to download the file. In Chrome it won't display it in its PDF viewer - just gives the user the chance after downloading to open the file using whatever program they have associated with the ".pdf" file extension.

You should try using content-disposition header while streaming the PDF file to the browser. For example,
HttpContext.Current.Response.AddHeader("content-disposition", "attachment; filename=[ReportName].pdf");
// Code to stream pdf file content to the client
...
For more info about content disposition, see
http://www.jtricks.com/bits/content_disposition.html
http://greenbytes.de/tech/webdav/draft-reschke-rfc2183-in-http-latest.html

Since chrome is up to date with HTML5, we can use the shiny new download attribute!
Works

How to consume an asp.net image resizer with javascript

I use javascript/jquery to fill with html a web page. In IE works fine but in Firefox or Chrome the image is not shown wherever the image is shown when i click only the link:
http://localhost:12240/ImageResize.aspx?imgsrc=images/test.jpg&width=100
With javascript i create this html code:
<div class="item related-padding">
<div class="item-container item-0">
<div class="item-content" style="background:url(ImageResize.aspx?imgsrc=images/test.jpg&width=127) no-repeat;"></div>
<div class="item-type video"></div>
</div>
<div class="item-caption">Test</div>
</div>
I believe the problem is in C#, ASP.NET headers
Response.Buffer = true;
Response.Charset = "";
Response.Cache.SetCacheability(HttpCacheability.NoCache);
Response.ContentType = "image/jpg";
Random random = new Random();
int randomNumber = random.Next(1000000);
//Response.AddHeader("content-disposition", "attachment;filename=" + $randomNumber.ToString() + ".jpg");
/*resize happens here*/
bmp.Save(Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg);
Response.Flush();
Response.End();
bmp.Dispose();
image.Dispose();
any ideas?
All i want is to resize the image and output it as jpg

Add the <img src="ImageResize.aspx?imgsrc=images/test.jpg&width=127" alt=""/> instead of div with background image.

Your question misses the details needed for a to-the-point answer, but here are some hints you can look at:
Relative URIs in CSS are not always treated the same way, check with FireBug or an HTTP sniffer whether the correct relative URI is being retrieved. There used to be a difference here between IE and others, not sure it's still the same.
It's very likely that the error is in your JavaScript, which you don't show. You can check that with the javascript console and/or by printing out the result in an alert box or textbox and rendering that by hand, see what happens (look carefully at correct escaping).
You don't use an entity for the ampersand, though I can hardly imagine a browser would care about that
You don't do a Response.Clear(), which, if you create the response through a normal page request, can create a crippled response stream with headers and data from the page that you don't want there.
Test your code with a regular image on file, see if the CSS still holds (and the JavaScript, of course). Test JavaScript output and CSS separately to make sure to find the right guilty party (CSS, JS, server side C# or else).

How do I launch an .exe file on page load to save or run?

I have this lead generation form and after they give us their information, I would like the form's thank you page to popup a window where the user can save the file or open it.
This web page will be served from a Microsoft server so .net C# or javascript are options.
thx

I Assume, your problem is to display a thank you page, and also to open a new save / run dialog.
The below js code, / HTML code in the thank you page will render the thank you page, and make the browser request for the file mentioned in the URL. If that is configured properly as mentioned by others, it will prompt the dialog
Try
Javascript
document.write("<META HTTP-EQUIV=\"refresh\" content=\".1; URL=http://domain.come/my.exe\">");
HTML
<META HTTP-EQUIV="refresh" content=".1; URL=http://domain.come/my.exe">

Good luck getting any browser to open an .exe file... Warning Will Robinson... Warning...
Anyways, here's a snippet....
Response.Clear();
Response.ContentType = "application/octet-stream";
Response.AddHeader("Content-Disposition", "attachment; filename=" + downloadName);
while (dataToRead > 0)
{
if (Response.IsClientConnected)
{
fileLength = iStream.Read(buffer, 0, buffer.Length);
Response.OutputStream.Write(buffer, 0, fileLength);
Response.Flush();
dataToRead = dataToRead - fileLength;
}
else
{
dataToRead = -1;//prevent infinite loop if user disconnects
}
}
Edit: Ok, i suppose you could create the thank you page with a hidden button on it, inject some javascript to click that button upon load, which would then execute the code to dump the file into the response stream.

I would imagine your answer could be find in one of these previous questions
https://stackoverflow.com/search?q=force+download

You cannot launch a file on the users machine unless you have some ActiveX control or Java applet with permissions to do so installed.
You can create the file on your server and send it to the browser. The user will be prompted to save or open the file.