Silverlight, ActiveX, AIR, Sandbox, and Offline

1. Silverlight 2 stand-alone with ActiveX

Silverlight 2 stand-alone html application (it is better to change the .html to .hta, the host is MSHTA.EXE), using javascript (file mode, so full trust) to call activeX (note that this approach is not cross platform).

http://www.galasoft.ch/mydotnet/articles/article-2008042301.html
http://geekswithblogs.net/lbugnion/archive/2008/04/24/silverlight-running-standalone-full-trust-applications.aspx

http://blogs.microsoft.co.il/blogs/tamir/archive/2008/04/27/how-to-make-silverlight-be-air.aspx

2. If the requirement is not offline, but to access files and ports, can use special ActiveX with javascript.

3. Silverlight 3 OOB is not that useful

--a. Silverlight 3 OOB is within browser sandbox, so, cannot access file etc.
--b. Silverlight 3 OOB (out of browser) cannot use html/javascript, so, it cannot be used together with the hta technique.


4. The above is not cross-platform (but for intranet, it is good that it does not need to install any “extra” stuff), for that, AIR is the way to go.

5. Is it possible to use both AIR and pure Silverlight3? Not sure: (i) Can Silverlight3 be invoked from AIR? (ii) Silverlight cannot invoke AIR (sandbox), but it can save to the storage, and AIR can poll that. (iii) Silverlight cannot mash up AIR. (iv) AIR perhaps can mash up Silverlight. As a result, it looks like we can use AIR as the “shell” (base application), and invoke Silverlight screens (because it is in sandbox, so, it does not know other instances; so, the shell must be very lightweight and can be instantiated many times without performance issues).

6. For Serial port etc, it needs a generic "proxy" that translates port to socket(). Javascript can then use socket. Note that this makes it not portable. So, if we do not need offline feature, then, we can simply develop small ActiveXes to access things out of the sandbox, and use Silverlight for UI, and use javascript to glue things togother.