Action script on a button problem

1

I am trying to adapt the //code below
to a button directly
Can anyone see my problem?

thanks

on (release) = function() {
var startFrame = _imageLoader.main_03._currentframe
gotoAndPlay(_imageLoader.main_03._currentframe+1)
_imageLoader.main_03.onEnterFrame = function() {
if(_imageLoader.main_03._currentframe == startFrame+19) {
stop()
imageLoader.main_03.gotoAndPlay(11);
;
;
}
}
}

//stop();
//button_btn.onRelease = function() {
// var startFrame = _root._currentframe
// gotoAndPlay(_root._currentframe+1)
// _root.onEnterFrame = function() {
// if(_root._currentframe == startFrame+10) {
// stop();
// }
// }
//}