Setting is as easy as sending a message to the named object with the set or message functions, but retrieving the current information is much more difficult. One idea is to script a [grab] object into place and connect it to a [message] box and back to a dedicated inlet of your [js] object. If you only need this to work in a patching environment you can even parse the JSON text of your patch as demonstrated in this article. However this won't work with anything other than a maxpat file so if you need it to function in a standalone application this method will not work.
Thanks Luke for your reply.
unfortunately, this won't help me much, because i need to get the content of a comment box, and grab can't get it ; (and my js isn't in the same patch...)
ok, I'll find a workaround !