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Prevent Chrome from downloading files

I need to display files in a HTML page in an object tag.
I use C# MVC4 to send the file. In my code, I set the "Content-Type" and "Content-Disposition" headers.
When I set the Content-Type to something Chrome dosen't know, it will download the file, regardless of the "Content-Disposition" header.
HTML:
<div>
<object data="http://localhost/UncHelper?path=secrectPath\file.dwg"></object></div>
C#:
public override void ExecuteResult(ControllerContext context)
{
context.RequestContext.HttpContext.Response.AddHeader("Content-Type", _contentType);
context.RequestContext.HttpContext.Response.AddHeader("Content-Disposition", "inline; filename=\"" + _fileName + "\"");
context.HttpContext.Response.WriteFile(_uncPath);
context.HttpContext.Response.End();
}
When I try to display a pdf file (_contentType = application/pdf) everything is fine.
But when I try to display a .dwg (_contentType = application/dwg) Chrome will download the file. How can I prevent this?
(I don't want to set a HTML status of 203 based on the browser or anything like that.)
Thanks!

This is not possible, and is also a slight misunderstanding on your part i think. For a browser to be able to display a file, it first has to be downloaded.. This goes for all file types. For instance, if you were displaying an image of image/jpeg, with the disposition set to inline, the browser still downloads the image, and then displays it inline, instead of asking the user where he/she would like to save it. If the browser has no knowledge of how to display the file, this is not an option, and will default to the only other option, which is to ask the user where to save it.

how to open word document without dialogbox in asp.net?

I an trying to open word document on hyperlink click. Now below code is opening dialogbox ans asking for saving.
How to open directly word document without user asking dialogbox for saving or open? just need to popup with word doc.
Response.Clear()
Response.ContentType = "application\msword"
Dim file As New System.IO.FileInfo(Server.MapPath("/UserManual\Carangi Reunderwriting Website User Manual.docx"))
Response.AddHeader("Content-Disposition", "inline; filename=" + file.Name)
Response.AddHeader("Content-Length", file.Length.ToString())
Response.TransmitFile(file.FullName)
Response.Flush()
Response.End()

Browser settings can override the content-disposition header. You might want to check and see if your document opens inline in another browser or on another machine. Seems to me that conservative default settings these days should show a save dialog before opening a word document from a web page.

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

PDF in modal iframe renders blank in IE

EDIT 2
It appears that moving the object tag in the Dom is the cause of the problem. I added an iframe directly to the page and it works fine without any problems.
However, when I move that iFrame into a modal dialogue box (http://www.ericmmartin.com/projects/simplemodal/) the PDF disappears (the object tag no longer renders correctly).
So it appears that it's no longer a question about my handler, but more a question about why moving the "object" (or embed) tag in the DOM (which lives inside an iFrame) causes it to "blank-out."
Also, when the pdf is moved from the modal dialogue back to its original position, it appears correctly. So, perhaps I should focus more on the modal dialogue itself.
Thoughts? Thanks for your suggestions thus far.
EDIT 1
So I've made some modifications for testing.
I've got the iframe to output an object tag for pdf requests along with the server time.
Response.AddHeader("content-type", "text/html");
WebClient client = new WebClient();
Response.Write("<html><head></head><body><h1>"+ DateTime.Now.ToString() + "</h1><object height='100%' width='100%' name='plugin' data='" + Request.Url.ToString() + "&embed=true' type='application/pdf' /></body></html>");
Response.Flush();
Response.Close();
Response.End();
Now I get a page with the current time correctly, but the object only displays the PDF the first time after I publish the aspx page. So it appears to be some sort of caching issue? Except that the object isn't loading anything (not even the previously loaded PDF).
If right click on the iframe and refresh the page, the object loads up fine. (The same is true if I use an embed tag).
Original Question
I know there are a lot of questions on this...
streaming PDF data through an ASPX page
Server generated PDF not displaying in IFrame on aspx page on some (but not all )PCs
Displaying a PDF Document in ASP.net page
But they either weren't answered, or the answer didn't work.
Environment
.Net 4
Adobe 9.3.4
IIS 5.1
XP sp3
VS 2010
IE 8.0.6001.18702
Background
The pdf's I'm streaming come from a storage repository where the files don't have any extensions (this is done for security). I look up the file in the database and stream it back to the client via the following code:
Response.Clear();
WebClient client = new WebClient();
Byte[] buffer = client.DownloadData(sPath);
Response.AddHeader("content-length", buffer.Length.ToString());
Response.AddHeader("content-disposition", "inline;filename=" + fileName);
Response.AddHeader("expires", "0");
Response.AddHeader("Content-Type", "application/pdf"); //this is usually dynamic to support other types (doc, xls, txt, etc.)
Response.OutputStream.Write(buffer, 0, buffer.Length);
Response.Flush();
Response.Close();
Response.End();
This works for every file type (doc, txt, xls, html) when used directly in the browser or in the iframe (displayed as a modal popup) with the exception of pdf files. They do not work reliably when accessed via the iframe, but work fine when accessed directly in the browser.
The only time it does work is the first time I request a document after I publish the aspx page that is serving these files. All subsequent hits return a blank page (even from new tabs or browser windows). Firefox reliably displays the pdf every time regardless.
Attempted Solutions
I've tried various ways I of streaming the file:
Response.TransmitFile(sPath);
Response.WriteFile(sPath);
//As well as some others
I've tried adding .pdf to a parameter at the end of the request
http://www.myurl.aspx?File=test.pdf
I've tried making the URL unique by adding a time stamp
http://www.myurl.aspx?File=test.pdf&Unique=Friday__September_17__2010_12_02_16_PM
Un-Attempted
I've read about IIS compression causing problems, but it was for a newer version of IIS.
Didn't try using embed tag since I would like to stick to the iFrame if possible (The existing infrastructure uses it).
Any help would be greatly appreciated!!!
Thanks.

I had a similar problem that arose when the PDFs were streaming over SSL (IE only, FF didn't exhibit the issue) that was only solved by doing the following:
Response.ClearHeaders();
Response.ClearContent();
Response.Buffer = true;
Response.AppendHeader("Content-Disposition", "inline; attachment; filename=Filename.pdf");
Response.ContentType = "application/pdf";
Response.WriteFile(path);
Response.Flush();
Response.End();

So I gave up and decided to use a standard IE popup window instead.
window.open(URL, 'Window', 'height=' + pageHeight + ',width=' + pageWidth + ',top=0,left=0,resizable');
I had to render the pdfs in an object tag and everything else inside an iframe within the popup for it to work, but it works...
if (sDocType == "pdf")
{
Response.AddHeader("content-type", "text/html");
WebClient client = new WebClient();
Response.Write("<html style='margin:0px;padding:0px;'><head></head><body style='margin:0px;padding:0px;'><object height='100%' width='100%' name='plugin' data='" + Request.Url.ToString() + "&embed=true' type='" + zGetContentType(HttpContext.Current.Request.QueryString["docType"]) + "'><param name='src' value='" + Request.Url.ToString() + "&embed=true' />alt : <a href='" + Request.Url.ToString() + "&embed=true'>View</a></object></body></html>");
Response.Flush();
Response.Close();
Response.End();
}
else
{
Response.AddHeader("content-type", "text/html");
WebClient client = new WebClient();
Response.Write("<html style='margin:0px;padding:0px;'><head></head><body style='margin:0px;padding:0px;'><iframe frameborder='0' scrolling='no' height='100%' width='100%' src='" + Request.Url.ToString() + "&embed=true' /></body></html>");
Response.Flush();
Response.Close();
Response.End();
}

I'm not sure that you need to set the filename, especially if it doesn't have the .pdf extension. When streaming PDFs to browser in the past, I've always used this code:
Response.Clear();
Response.ContentType = "application/pdf";
Response.BinaryWrite(pdfBuffer);
Response.Flush();
Otherwise, there's a possibility that something has hosed over the registry settings for the application/pdf CLSID on the client computer.

I was able to solve a similar problem (pdf inside of modal window internet explorer)
by taking out the iframe. Instead, load the pdf into an html object element.
see the link below:
http://intranation.com/test-cases/object-vs-iframe/
To sum it up:
The setup that did not work:
jQuery floatbox, loads html fragment with iframe, load aspx page into iframe, load pdf into aspx page
The setup that now works:
jQuery floatbox, loads html fragment, append object element.
before appending the object element, set data
attribute of object element to the aspx page url

Export ListView to Word

To export a gridview to Excel, the reponse content type can be changed to "application/vnd.xls" and then rendered using gridName.RenderControl. Is there any reason this same approach cannot/should not be taken for rendering a listview out to word?
Is there another preferred method for exporting a listview to word?
UPDATE: I have verified that this will work with Word; however, when opening the file, Word displays the html tags (along with the content) from the listview. Below is the code.
Response.Clear();
Response.AddHeader("content-disposition", "attachment;filename=test.doc");
Response.Charset = "";
Response.ContentType = "application/msword";
var stringWriter = new StringWriter();
var htmlWriter = new HtmlTextWriter(stringWriter);
listView.RenderControl(htmlWriter);
Response.Write(stringWriter.ToString());
Response.End();

The same technique will also work for Microsoft Word. The reason this works the way it does, it that both applications will open and read HTML as the source document format. The filename and the content type are set by the website so that the browser knows the application needed to open the file.