Silverlight OOB updates when using MEF / PRISM

Question

I am working on a prototype for Silverlight OOB application. To modularize the application either PRISM or MEF or both will be used. When a new version of the application is available, CheckAndDownloadUpdateAsync can assist in downloading the latest version in OOB scenario.

How does updates work if only a new version of an application module is available? Is there a known functionality and/or strategy to be used to download new modules?

Answer 1

You can roll your own update detection, by having a small file on your server next to the XAP for your app, that contains the latest version. For example:

http://localhost/myawesomeapp.xap
http://localhost/myawesomeapp.xap.ver

When you want to check for updates without downloading them, you can always hit the .ver file, check the version listed in it and if newer then the current running app, show the Update button to the user.

Note that this approach also would allow you to create more advanced scenarios, like prompting the user to upgrade to a different version of the app (Pro for example) or that they need to upgrade their Silverlight to get the latest.

And if you have multiple apps, you can list all of them in that file and do cross-promotion between your apps.