一、需求
轮播图如下图所示，需求是每隔一秒轮播图自动切换一次
二、代码素材
以下是缺失JS部分的代码，感兴趣的小伙伴可以先自己试着写一写
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>轮播图点击切换</title>
<style>
* {
box-sizing: border-box;
}
.slider {
width: 560px;
height: 400px;
overflow: hidden;
}
.slider-wrapper {
width: 100%;
height: 320px;
}
.slider-wrapper img {
width: 100%;
height: 100%;
display: block;
}
.slider-footer {
height: 80px;
background-color: rgb(100, 67, 68);
padding: 12px 12px 0 12px;
position: relative;
}
.slider-footer .toggle {
position: absolute;
right: 0;
top: 12px;
display: flex;
}
.slider-footer .toggle button {
margin-right: 12px;
width: 28px;
height: 28px;
appearance: none;
border: none;
background: rgba(255, 255, 255, 0.1);
color: #fff;
border-radius: 4px;
cursor: pointer;
}
.slider-footer .toggle button:hover {
background: rgba(255, 255, 255, 0.2);
}
.slider-footer p {
margin: 0;
color: #fff;
font-size: 18px;
margin-bottom: 10px;
}
.slider-indicator {
margin: 0;
padding: 0;
list-style: none;
display: flex;
align-items: center;
}
.slider-indicator li {
width: 8px;
height: 8px;
margin: 4px;
border-radius: 50%;
background: #fff;
opacity: 0.4;
cursor: pointer;
}
.slider-indicator li.active {
width: 12px;
height: 12px;
opacity: 1;
}
</style>
</head>
<body>
<div class="slider">
<div class="slider-wrapper">
<img src="./images/slider01.jpg" alt="" />
</div>
<div class="slider-footer">
<p>对人类来说会不会太超前了？</p>
<ul class="slider-indicator">
<li class="active"></li>
<li></li>
<li></li>
<li></li>
<li></li>
<li></li>
<li></li>
<li></li>
</ul>
<div class="toggle">
<button class="prev"><</button>
<button class="next">></button>
</div>
</div>
</div>
<script>
// 1. 初始数据
const sliderData = [
{ url: './images/slider01.jpg', title: '对人类来说会不会太超前了？', color: 'rgb(100, 67, 68)' },
{ url: './images/slider02.jpg', title: '开启剑与雪的黑暗传说！', color: 'rgb(43, 35, 26)' },
{ url: './images/slider03.jpg', title: '真正的jo厨出现了！', color: 'rgb(36, 31, 33)' },
{ url: './images/slider04.jpg', title: '李玉刚：让世界通过B站看到东方大国文化', color: 'rgb(139, 98, 66)' },
{ url: './images/slider05.jpg', title: '快来分享你的寒假日常吧~', color: 'rgb(67, 90, 92)' },
{ url: './images/slider06.jpg', title: '哔哩哔哩小年YEAH', color: 'rgb(166, 131, 143)' },
{ url: './images/slider07.jpg', title: '一站式解决你的电脑配置问题！！！', color: 'rgb(53, 29, 25)' },
{ url: './images/slider08.jpg', title: '谁不想和小猫咪贴贴呢！', color: 'rgb(99, 72, 114)' },
]
</script>
</body>
</html>三、算法思路
1、将代码素材在浏览器中打开，并按F12进入开发者模式，分析各个HTML标签在轮播图中的位置及作用
2、获取相关元素
3、利用间歇函数实现一秒切换一次的功能，间歇函数中的计数器 i 配合素材代码中的数组对象实现图片和文字等样式的顺序播放
四、完整代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>轮播图点击切换</title>
<style>
* {
box-sizing: border-box;
}
.slider {
width: 560px;
height: 400px;
overflow: hidden;
}
.slider-wrapper {
width: 100%;
height: 320px;
}
.slider-wrapper img {
width: 100%;
height: 100%;
display: block;
}
.slider-footer {
height: 80px;
background-color: rgb(100, 67, 68);
padding: 12px 12px 0 12px;
position: relative;
}
.slider-footer .toggle {
position: absolute;
right: 0;
top: 12px;
display: flex;
}
.slider-footer .toggle button {
margin-right: 12px;
width: 28px;
height: 28px;
appearance: none;
border: none;
background: rgba(255, 255, 255, 0.1);
color: #fff;
border-radius: 4px;
cursor: pointer;
}
.slider-footer .toggle button:hover {
background: rgba(255, 255, 255, 0.2);
}
.slider-footer p {
margin: 0;
color: #fff;
font-size: 18px;
margin-bottom: 10px;
}
.slider-indicator {
margin: 0;
padding: 0;
list-style: none;
display: flex;
align-items: center;
}
.slider-indicator li {
width: 8px;
height: 8px;
margin: 4px;
border-radius: 50%;
background: #fff;
opacity: 0.4;
cursor: pointer;
}
.slider-indicator li.active {
width: 12px;
height: 12px;
opacity: 1;
}
</style>
</head>
<body>
<div class="slider">
<div class="slider-wrapper">
<img src="./images/slider01.jpg" alt="" />
</div>
<div class="slider-footer">
<p>对人类来说会不会太超前了？</p>
<ul class="slider-indicator">
<li class="active"></li>
<li></li>
<li></li>
<li></li>
<li></li>
<li></li>
<li></li>
<li></li>
</ul>
<div class="toggle">
<button class="prev"><</button>
<button class="next">></button>
</div>
</div>
</div>
<script>
// 1. 初始数据
const sliderData = [
{ url: './images/slider01.jpg', title: '对人类来说会不会太超前了？', color: 'rgb(100, 67, 68)' },
{ url: './images/slider02.jpg', title: '开启剑与雪的黑暗传说！', color: 'rgb(43, 35, 26)' },
{ url: './images/slider03.jpg', title: '真正的jo厨出现了！', color: 'rgb(36, 31, 33)' },
{ url: './images/slider04.jpg', title: '李玉刚：让世界通过B站看到东方大国文化', color: 'rgb(139, 98, 66)' },
{ url: './images/slider05.jpg', title: '快来分享你的寒假日常吧~', color: 'rgb(67, 90, 92)' },
{ url: './images/slider06.jpg', title: '哔哩哔哩小年YEAH', color: 'rgb(166, 131, 143)' },
{ url: './images/slider07.jpg', title: '一站式解决你的电脑配置问题！！！', color: 'rgb(53, 29, 25)' },
{ url: './images/slider08.jpg', title: '谁不想和小猫咪贴贴呢！', color: 'rgb(99, 72, 114)' },
]
const img=document.querySelector('.slider-wrapper img')
const p=document.querySelector('.slider-footer p')
const ul=document.querySelector('.slider-footer .slider-indicator')
const footer=document.querySelector('.slider-footer')
let i=0
setInterval(()=>{
i = (i + 1) % 8
img.src=`./images/slider0${i+1}.jpg`
p.innerHTML=sliderData[i].title
footer.style.backgroundColor=sliderData[i].color
//注意classList.remove()括号中的类名不需要加点号！
document.querySelector('.slider-indicator .active').classList.remove('active')
document.querySelector(`.slider-indicator li:nth-child(${i+1})`).classList.add('active')
},1000)
</script>
</body>
</html>
