var gift=['iphone','ipad','三星note7','三星平板电脑','佳能相机','谢谢参与'],
	play=document.getElementById('play'),
	stop=document.getElementById('stop')
	title=document.getElementById('title'),
	timer=null,
	flag=0;
window.onload=function(){		//封装一个类
	var eventUntil={
		addEvent:function(element,type,hander){
				if(element.addEventListener){
						element.addEventListener(type,hander);
				}else if(element.attachEvent){
						element.attachEvent('on'+type,hander);
				}else{
						element['on'+type]=hander;
				}
		},
	}
	eventUntil.addEvent(play,'click',playFun())//鼠标事件
}
//getrandom函数
function getrandom(){
	var myrandom=Math.floor(Math.random()*gift.length);
}
//开始函数
function playFun(){
			clearInterval(timer);
			timer=setInterval(function(){
				var random=Math.floor(Math.random()*gift.length)},50);
			title.innerHTML=gift[random];
};

HTML和老师基本一样，我用了input标签，