### css
?
* {
margin: 0;
padding: 0;
}
?
.box {
margin: 20px auto;
}
?
.list {
height: 20px;
width: 200px;
}
?
.list li {
width: 64px;
float: left;
list-style: none;
border: 1px solid red;
}
?
?
?
.box div {
width: 200px;
height: 200px;
background: lightblue;
text-align: center;
line-height: 200px;
display: none;
}
?
### html
?
<div class="box">
<ul class="list">
<li style="background: blueviolet;">项目1</li>
<li>项目2</li>
<li>项目3</li>
</ul>
<div style="display: block;">
项目1
</div>
<div>
项目2
</div>
<div>
项目3
</div>
</div>
?
### js
?
var Ali = document.getElementsByTagName("li");
var Adiv = document.querySelectorAll(".box div");
for (let i = 0; i < Ali.length; i++) {
// 把循环的数字赋给Ali中index
Ali[i].index = i;
// console.log(Ali[i].index);
Ali[i].onclick = function () {
for (let i = 0; i < Ali.length; i++) {
Ali[i].style.background = ‘‘;
Adiv[i].style.display = ‘none‘;