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為什么這樣無法實現呢？求解答 /(ㄒoㄒ)/~~ 代碼如下

<body>
?? ?<div class='title'>開始抽獎啦！</div>
?? ?<div class='btns' >
?? ??? ?<span class='start'>開始</span>
?? ??? ?<span class='stop'>結束</span>
?? ?</div>
?? ?<script>
?? ?var data=['紅米','白米','小米','大米','黑米','恭喜抽中騷豬','謝謝惠顧'];
?? ?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

關四鳥
2019-09-02

<body><div?class='title'>開始抽獎啦！</div>
<div?class='btns'?><button?class='start'>開?始</button>
<button?class='stop'>結?束</button></div>
<script>
var?data=['紅米','白米','小米','大米','黑米','恭喜抽中騷豬','謝謝惠顧'];
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中間有s，它是一個對象集合。上述是改過之后的代碼，你可以繼續寫完stop