Tool to invoke actions in Flash swf via JavaScript

I 开发者_开发知识库have a flash swf file without access to it's source. Can I use only JavaScript to invoke/initiate the action of the flash functions within the swf file?

Or does the swf need active listeners to respond to JavaScript?

You cannot communicate with an SWF (at least an AVM2 (AS3 based) SWF) unless it has registered callback methods in it. The ExternalInterface class has an addCallback() method that:

Registers an ActionScript method as callable from the container. After a successful invocation of addCallBack(), the registered function in Flash Player can be called by JavaScript or ActiveX code in the container.