Components.classes[ possibleValues ]?

Add-ons Development
#1

can I have a list of what is possible
in Components.classes[ … ] and what is the meaning?

Components.classes[ possibleValues ]?

Thanks

#2

There’s no definitive list of what’s possible there, as every extension could add an infinite amount of entries to that list. Many built in values are undocumented, many are documented under https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference.

I think it’s possible to list all values during runtime, but I am not sure of the best method.

#3

in an Add-on I found these …
var prefManager = Components.classes[ "@mozilla.org/preferences-service;1" ].getService( Components.interfaces.nsIPrefBranch );
var timer = Components.classes[ "@mozilla.org/timer;1" ].createInstance( Components.interfaces.nsITimer );

and in another Add-on this, but this doesn’t work, why?
var extensionManager = Components.classes[ "@mozilla.org/extensions/manager;1" ].getService( Components.interfaces.nsIExtensionManager );

#4

What kind of extensions are you writing?
In WebExtensions you don’t have access to XPCOM (the Components global),
in SDK extensions there are better modules to use before resorting to XPCOM (and you need to use special methods).
Else it should work.

#5

How about

Object.getOwnPropertyNames(Components.classes)