<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
*{
padding:0;
margin:0;
list-style: none;
}
#box1{
500px;
height:500px;
border:1px solid red;
}
#box1 input{
background: yellow;
}
#box1 .active{
background: red;
}
#box1 div{
300px;
height:300px;
background: red;
font-size: 50px;
text-align: center;
line-height: 300px;
display: none;
}
#box1 .show{
display: block;
}
</style>
</head>
<body>
<div id="box1">
<input type="button" value="按钮1" class="active">
<input type="button" value="按钮2">
<input type="button" value="按钮3">
<div class="show">1</div>
<div>2</div>
<div>3</div>
</div>
<script>
var oBox = document.getElementById('box1');
var aBtn = oBox.getElementsByTagName('input');
var aBox = oBox.getElementsByTagName('div');
for(var i=0; i<aBtn.length; i++){
aBtn[i].index = i;
aBtn[i].onclick = function () {
for(var i=0; i<aBtn.length; i++){
aBtn[i].className = '';
aBox[i].className = '';
}
aBox[this.index].className = 'show';
this.className = 'active';
}
}
</script>
</body>
</html>