Question

I am trying to download and store an image file in VS2008, .NET Framework 3.5, but the resultant file is too small.

When I navigate to http://www-nass.nhtsa.dot.gov/nass/cds/GetBinary.aspx?Image&ImageID=682367204 in my browser, I am able to download it as a 68k file. However, using the following code, I get a file just under 4k:

using (WebClient webClient = new WebClient()) {
  webClient.DownloadFile("http://www-nass.nhtsa.dot.gov/nass/cds/GetBinary.aspx?Image&ImageID=682367204", @"D:\\682367204.jpg");
}

UPDATE: WebClient with credentials still not downloading file likely describes the source of (and solution to) my problem.

Answer 1

Well I guess this is due to authorization restriction.

The reason why your code, Carlos and myself get a 4K file is because we have not the rights to access the requested file.

I guess you’ve used a sort of login procedure to access the site with your browser, or are on a trusted network allowing the site to use your NT tokens.

What seems to confirm this hypothesis is that when I change the extension of the GetBinary.aspx file to jpeg I obtain a kind of “forbidden” icon.

So you may have to do more work from your code to authenticate.

EDIT: using the ‘NIX file utility with Cygwin gives this :

JPEG image data, JFIF standard 1.01

So what you get is indeed a JPEG image.