Javascript submit XFDF every few minutes?

Question

I programmatically create a PDF and display it to a person on my web app. I use javascript to setup a submit of the XFDF data to another web page which then saves the data to a database so I can recall it later and repopulate the PDF when the bring it up again. Sometimes these PDFs can take a long time to fill out so I was wondering, is there a way to use Javascript to be able to automatically send the XFDF to a file or web page every few minutes as sort of an autosave feature but not take them away from the PDF. I used to program all the form fields in HTML and use Javascript to iterate through the fields and save it to the server every few minutes, but now that I'm displaying the PDF in its native format, I'd like to incorporate something like this so that users won't lose all their changes should their computer die at a certain point or they lose connection to the web app at some point.
I'm using C# and asp.net BTW.
John

Answer 1

You can use the submitForm JavaScript method to submit the data: http://livedocs.adobe.com/acrobat_sdk/9.1/Acrobat9_1_HTMLHelp/JS_API_AcroJS.88.537.html
The response from your server script could be just the HTTP "204 No Content" type header.
To submit at regular intervals, you can use the app.setInterval method: http://livedocs.adobe.com/acrobat_sdk/9.1/Acrobat9_1_HTMLHelp/JS_API_AcroJS.88.165.html
Finally, the user will have to allow the submit action, the first time at least.