XPConnect:nsIProfile

From MDC

• XPCOM reference: nsIProfile

Get a hold of the profile manager:

js> var Cc = Components.classes;
js> var Ci = Components.interfaces;
js> var rc = Cc["@mozilla.org/profile/manager;1"];
js> var rs = rc.getService(Ci.nsIProfile);

Now, we want to call getProfileList.

But getProfileList has a funky signature:

void getProfileList ( out PRUint32 length , retval arrayof PRUnichar* profileNames )

JavaScript doesn't have pointers, so you can't pas a variable as the length argument, and end up with the value.

We use a trick instead; You pass it a blank object, and it will set the "value" attribute of the object.

js> var obj = Object();
js> obj
[object Object]
js> rs.getProfileList(obj)
default
js> obj.value
1

The "1" result means, "the returned array had one item in it."

See where it says "default" above, in response to rs.getProfileList? That "default" is not just a string, it's actually an array.

js> var ar = rs.getProfileList(obj)
js> ar
default

If you had multiple items in there, it might look like this:

js> ar
default, Ned, Josh, Sally
js> obj.value
4

You can learn more about how XPConnect binds XPCOM function signatures to Javascript objects:

 http://www.mozilla.org/scriptable/faq.html