<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>轮播图</title>
<style>
* {
margin: 0;
padding: 0;
}
body {
display: flex;
justify-content: center;
align-items: center;
flex-direction: column;
}
ul,
ol,
li {
list-style: none;
}
img {
width: 100%;
height: 100%;
display: block;
}
header {
width: 100%;
height: 50px;
text-align: center;
}
.banner {
width: 800px;
height: 500px;
position: relative;
margin: 50px 0;
}
.banner > ul {
width: 100%;
height: 100%;
position: relative;
}
.banner > ul > li {
width: 100%;
height: 100%;
position: absolute;
left: 0;
top: 0;
opacity: 0;
transition: opacity .5s linear;
}
.banner > ul > li.active {
opacity: 1;
}
.banner > ol {
width: 200px;
height: 30px;
position: absolute;
left: 30px;
bottom: 30px;
background-color: rgba(0, 0, 0, .5);
display: flex;
justify-content: space-around;
align-items: center;
border-radius: 15px;
}
.banner > ol > li {
width: 20px;
height: 20px;
background-color: #fff;
border-radius: 50px;
}
.banner > ol > li.active {
background-color: orange;
}
.banner > div {
width: 40px;
height: 60px;
position: absolute;
top: 50%;
transform: translateY(-50%);
background-color: rgba(0, 0, 0, .5);
display: flex;
justify-content: center;
align-items: center;
font-size: 30px;
color: #fff;
text-align: center;
line-height: 60px;
}
.banner > div.left {
left: 0;
}
.banner > div.right {
right: 0;
}
</style>
</head>
<body>
<header><h1>欢欢商城</h1></header>
<div class="banner">
<!-- 图片区域 -->
<ul class="imgBox">
<li class="active"><img
src="https://img14.360buyimg.com/pop/s1180x940_jfs/t1/31576/24/16120/43491/62c24333E0d61b301/1c278ce900303beb.jpg.webp"
alt=""></li>
<li><img
src="https://img14.360buyimg.com/pop/s1180x940_jfs/t1/217320/3/17745/94780/6270f940Eb607dc65/b7ae05d4a569739c.jpg.webp"
alt=""></li>
<li><img
src="https://imgcps.jd.com/ling4/100008348542/5Lqs6YCJ5aW96LSn/5L2g5YC85b6X5oul5pyJ/p-5bd8253082acdd181d02f9ee/73226ace/cr/s/q.jpg"
alt=""></li>
<li><img
src="https://imgcps.jd.com/ling4/100025520132/5Lqs6YCJ5aW96LSn/5L2g5YC85b6X5oul5pyJ/p-5bd8253082acdd181d02f9ff/aa4524e6/cr/s/q.jpg"
alt=""></li>
</ul>
<!-- 焦点区域 -->
<ol>
<li data-i="0" data-name="point" class="active"></li>
<li data-i="1" data-name="point"></li>
<li data-i="2" data-name="point"></li>
<li data-i="3" data-name="point"></li>
</ol>
<!-- 左右切换按钮 -->
<div class="left"><</div>
<div class="right">></div>
</div>
<script>
// 获取到所有承载图片的li和所有承载焦点的li
var imgs = document.querySelectorAll('ul>li');
var points = document.querySelectorAll('ol>li');
var banner = document.querySelector('.banner');
var left = document.querySelector('.left');
var right = document.querySelector('.right');
// 准备一个变量，表示当前是第几张，默认是0，因为默认显示的是索引第0张
var index = 0;
// 书写一个切换一张的函数
// 约定：
// 参数为true，我们切换下一张
// 参数为false，我们切换上一张
// 参数为数字，我们切换到指定索引的那一张
function changeOne(type) {
// 1.让当前这一张消失
imgs[index].className = ''
points[index].className = ''
// 2.根据type传递来的参数，来切换index的值
if (type === true) {
index++;
} else if (type === false) {
index--;
} else {
index = type;
}
// 判定一下index的边界值
if (index >= imgs.length) {
index = 0;
}
if (index < 0) {
index = imgs.length - 1;
}
// 3.让改变后的这一张显示出来
imgs[index].className = 'active';
points[index].className = 'active';
}
// 给 轮播图区域 盒子绑定点击事件
banner.onclick = function (e) {
// console.log('点击事件');
// 判断点击的是左按钮
if (e.target.className === 'left') {
console.log('点击的是左按钮');
// 切换上一张，调用changeOne 方法传递参数为false
changeOne(false);
}
// 判断点击的是右按钮
if (e.target.className === 'right') {
console.log('点击的是右按钮');
// 切换下一张，调用changeOne 方法传递参数为true
changeOne(true);
}
// 判断点击的是焦点盒子
if (e.target.dataset.name === 'point') {
console.log('点击的是焦点盒子');
// 拿到自己身上记录的索引
var i = e.target.dataset.i - 0;
// 切换某一种，调用changeOne方法传递参数为要切换的索引
changeOne(i);
}
}
// 自动切换功能
timer = setInterval(function () {
// 切换到下一张
changeOne(true)
}, 3000);
// 显示，隐藏左右按钮
banner.addEventListener('mouseenter', function () {
left.style.display = 'block';
right.style.display = 'block';
clearInterval(timer);
})
banner.addEventListener('mouseleave', function () {
left.style.display = 'none';
right.style.display = 'none';
timer = setInterval(function () {
// 切换到下一张
changeOne(true)
}, 3000);
})
</script>
</body>
</html>
原创文章，作者：kirin，如若转载，请注明出处：https://blog.ytso.com/275463.html