every dear friend!! need you warm heart and warm head. First I write a firefox extension which realize a function by javascript, then I want to call this js function by a c++ client, for example, there is button in the c++ client, when I click the button, the function in the js is called. From website I know xpcome has to be used, the call sequence is "c++ client" calling "xpcom" calling "javascript", right? I am a little puzzled, would you like explain? or better if there is souce code example. Thank you very ver much!