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为什么这样无法实现呢？求解答 /(ㄒoㄒ)/~~ 代码如下

<body>
   <div class='title'>开始抽奖啦！</div>
   <div class='btns' >
       <span class='start'>开始</span>
       <span class='stop'>结束</span>
   </div>
   <script>
   var data=['红米','白米','小米','大米','黑米','恭喜抽中骚猪','谢谢惠顾'];
   window.onload=function(){

       var start=document.getElementsByClassName('start');
       var stop=document.getElementsByClassName('stop');
       var title=document.getElementsByClassName('title');
       start.onclick=function(){
           timer=setInterval(function(){
               var random=Math.floor(Math.random()*data.length);
               console.log(random);
               // title.innerHTML=data[random];
           },50);
       }
   }
   </script>
</body>

慕仔1126745

2019-08-10

源自：DOM事件探秘 4-4

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1 回答

关四鸟
2019-09-02

<body><div class='title'>开始抽奖啦！</div>
<div class='btns' ><button class='start'>开 始</button>
<button class='stop'>结 束</button></div>
<script>
var data=['红米','白米','小米','大米','黑米','恭喜抽中骚猪','谢谢惠顾'];
window.onload=function(){var start=document.getElementsByClassName('start');
var stop=document.getElementsByClassName('stop');
var title=document.getElementsByClassName('title');
start[0].onclick=function(){function timer(){var random=Math.floor(Math.random()*data.length);
console.log(random);
title[0].innerHTML=data[random];}setInterval(timer,50);}}
</script>
</body>

你注意看getElementsByClassName中间有s，它是一个对象集合。上述是改过之后的代码，你可以继续写完stop