http://asgamer.com/2009/using-string-variables-to-call-functions-in-as3
同場加映 apply function (try it)
Tweenlite.to(mc, ….)
個 mc 都係玩 apply 咋
http://troyworks.com/blog/2008/01/03/as3-functionapply/
http://www.adobe.com/livedocs/flash/9.0/ActionScriptLangRefV3/Function.html