声音加载

var sound:Sound = new Sound(new URLRequest("music/bg.mp3"),new SoundLoaderContext (2000));
var chan:SoundChannel=sound.play();
var pausePosition:int;
an_btn.addEventListener(MouseEvent.CLICK,onClick);
function onClick(e:MouseEvent) {
       if (mc.currentFrame==1) {
          mc.gotoAndStop(2);
          pausePosition= chan.position;
          chan.stop();
     } else {
          mc.gotoAndStop(1);
          chan=sound.play(pausePosition);
     }
}