请教flash控制在某一帧停留多少秒的Action

var pos = 218; //记录哪个frame要停留
var timeout = 3000; //设定停留秒数
onEnterFrame = function() {
if(_currentframe == pos) {
stop();
var a = setInterval(function() {play();clearInterval(a);}, timeout);
onEnterFrame = null;
}
}