title: ASP.NET MVC FileStreamResult, fileDownloadName is not used
body: <p>The following returns a PDF which the browser tries to directly display inline. This works correctly. However, if I try to download the file, the download name is not "myPDF.pdf", but instead the ID in the route (myapp/controller/PDFGenerator/ID). Is it possible to set the file download name to be "myPDF.pdf"?</p>
  
  <pre><code>public FileStreamResult PDFGenerator(int id)
  {
      MemoryStream ms = GeneratePDF(id);
  
      byte[] file = ms.ToArray();
      MemoryStream output = new MemoryStream();
      output.Write(file, 0, file.Length);
      output.Position = 0;
      HttpContext.Response.AddHeader("content-disposition", 
      "inline; filename=myPDF.pdf");
  
      return File(output, "application/pdf", fileDownloadName="myPDF.pdf");
  }
  </code></pre>