I am upgrading a DNN Ajax datagrid page to a Silverlight2 datagrid application within DNN 4.8.4.  The DNN site is running on my local XP SP2 PC under /localhost.

I am storing documents ( .txt, pdf, xls, doc ) files in a SqlServer 2005 db in an image field.  I read the Sql documents table and display the document description and documentID (primary key) in a Silverlight datagrid.  The user selects a grid row ( docID ) and pushes a button.

1)  Silverlight app opens a new browser - DNN displayDoc.aspx page

                Uri uri = new Uri("http://localhost/myDNN/DesktopModules/Docs/displayDoc.aspx");

                HtmlWindow window = HtmlPage.Window;

                window.Navigate(uri, "_blank");

2) The displayDoc code behind page "retrieves" the "docID" key, reads the document from the database into a byte array and displays in the newly opened browser via Response.BinaryWrite.

My orignal DNN .aspx module used Session variable to hold the docID.

I have not been able to get docID data field from Silverlight to a newly open browser ASPX page.  I tried 2 methods:

1) The SilverLight app called a DNN Webservice.  The Webservice then stored the value:  Session(DocKey) = docID.  This does not work because the Webservice call is asynchronous i.e the new ASPX browser page may get a stale Session(DocKey) value  ( the async webservice has not completed the Session write).  I put a 2 second SLEEP after the call to the Webservice and before opening the new browser window but this did not work.

2) Isolated storage.

Dim isoFile As IsolatedStorageFile = IsolatedStorageFile.GetMachineStoreForApplication()

This was the only property that was common between the page.xaml.vb and App_Code\webserviceSessionFunction.vb.   But I get this error:

" GetUserStoreForApplication Unable to determine application identity of the caller."

Googling indicates this only works for ClickOnce apps.  I don't know how this relates to my DNN site.

Thanks for any help.

Michael,

The base functionality I need is to retrieve a document (Excel, Word, PDF ... ) from a database and display.  When the document is retrieved, the diplaying page should function like the base document.  For example,  if opening an Excel document, the page would have full Excel functionality.  That is how my current implementation works when the Response.BinaryWrite streams the databased byte data to the newly opened window.

Thanks to your excellent tutorials, I have already implemented Webservices within DNN.

How do I display a functioning Excel or Word document in a Silverlight page if I use WebServices to retrieve the byte stream from the database?

Michael,

I have not found an Excel or Word Silverlight display control.

I did "solve" this by breaking up the program logic into 2 distinct functions.  This seems to get over the non-determanistic webservice async issue.

1) When a datagrid row is selected, I call the Webservice to set the Session["docID"] variable.

2) The user must click a "Display" button to open the new browser page.  The code behind reads the Session["docID"] variable set in step #1.  The correct document is displayed.

There is some wasted webservice calls (step 1), if the use clicks to different grid rows before finally clicking the display button (step 2 ).

If there are other ideas and implementations, please post.

Thanks