<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<style>
* {
margin: 0;
padding: 0;
}
/* li {
list-style: none;
} */
.banner {
background-color: red;
width: 700px;
height: 500px;
margin: 0 auto;
position: relative;
}
.ul li {
width: 700px;
height: 500px;
font-size: 60px;
color: white;
line-height: 500px;
text-align: center;
list-style: none;
display: none;
}
.ol {
width: 100%;
position: absolute;
bottom: 10px;
display: flex;
justify-content: center;
line-height: 30px;
}
.ol li {
list-style: none;
width: 20px;
height: 20px;
background-color: aliceblue;
border-radius: 50%;
margin: 10px;
}
.span1 {
position: absolute;
left: 0;
top: 50%;
margin-top: -20px;
width: 40px;
height: 30px;
text-align: center;
line-height: 30px;
background: rgba(0, 0, 0, 0.3)
}
.span2 {
position: absolute;
right: 0;
top: 50%;
margin-top: -20px;
width: 40px;
height: 30px;
line-height: 30px;
text-align: center;
background: #0000004d
}
.ul .show {
display: block !important;
}
.ol .active {
background-color: green;
}
</style>
</head>
<body>
<div class="banner">
<ul class="ul">
<li class="show">1</li>
<li>2</li>
<li>3</li>
<li>4</li>
</ul>
<ol class="ol">
<li class="active"></li>
<li></li>
<li></li>
<li></li>
</ol>
<span class="span1">
<
</span>
<span class="span2">
>
</span>
</div>
<script>
var oul = document.querySelectorAll('.ul li')
var ool = document.querySelectorAll('.ol li')
var prev = document.querySelector('.span1')
var next = document.querySelector('.span2')
var t
var index = 0
//实现点击切图换图片
for (var i = 0; i < ool.length; i++) {
ool[i].index = i
ool[i].onclick = function () {
clearInterval(t)
for (var j = 0; j < ool.length; j++) {
ool[j].classList.remove('active')
oul[j].classList.remove('show')
}
this.classList.add('active')
index = this.index //不能var index
oul[index].classList.add('show')
}
}
//实现自动换图片
clearInterval(t)
t = setInterval(function () {
index++
if (index >= ool.length) {
index = 0
}
for (var j = 0; j < ool.length; j++) {
ool[j].classList.remove('active')
oul[j].classList.remove('show')
}
ool[index].classList.add('active')
oul[index].classList.add('show')
}, 2000)
prev.onclick = function () {
index--
if (index <= 0) {
index = 3
}
for (var j = 0; j < ool.length; j++) {
ool[j].classList.remove('active')
oul[j].classList.remove('show')
}
ool[index].classList.add('active')
oul[index].classList.add('show')
}
next.onclick = function () {
index++
if (index >= 4) {
index = 0
}
for (var j = 0; j < ool.length; j++) {
ool[j].classList.remove('active')
oul[j].classList.remove('show')
}
ool[index].classList.add('active')
oul[index].classList.add('show')
}
</script>
</body>
</html>
