index.html
<!DOCTYPE html>
<html lang="ja">
<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>My Carousel</title>
<link rel="stylesheet" href="css/style.css">
</head>
<body>
<section class="carousel">
<div class="container">
<ul>
<li><img src="img/pic1.png"></li>
<li><img src="img/pic2.png"></li>
<li><img src="img/pic3.png"></li>
<li><img src="img/pic4.png"></li>
</ul>
<button id="prev">«</button>
<button id="next">»</button>
</div>
<nav>
</nav>
</section>
<script src="js/main.js"></script>
</body>
</html>js/main.js
'use strict';
{
const next = document.getElementById('next');
const prev = document.getElementById('prev');
const ul = document.querySelector('ul');
const slides = ul.children;
const dots = [];
let currentIndex = 0;
function updateButtons() {
prev.classList.remove('hidden');
next.classList.remove('hidden');
if (currentIndex === 0) {
prev.classList.add('hidden');
}
if (currentIndex === slides.length - 1) {
next.classList.add('hidden');
}
}
function moveSlides() {
const slideWidth = slides[0].getBoundingClientRect().width;
ul.style.transform = `translateX(${-1 * slideWidth * currentIndex}px)`;
}
function setupDots() {
for (let i = 0; i < slides.length; i++) {
const button = document.createElement('button');
button.addEventListener('click', () => {
currentIndex = i;
updateDots();
updateButtons();
moveSlides();
});
dots.push(button);
document.querySelector('nav').appendChild(button);
}
dots[0].classList.add('current');
}
function updateDots() {
dots.forEach(dot => {
dot.classList.remove('current');
});
dots[currentIndex].classList.add('current');
}
updateButtons();
setupDots();
next.addEventListener('click', () => {
currentIndex++;
updateButtons();
updateDots();
moveSlides();
});
prev.addEventListener('click', () => {
currentIndex--;
updateButtons();
updateDots();
moveSlides();
});
window.addEventListener('resize', () => {
moveSlides();
});
}css/style.css
.carousel {
width: 80%;
margin: 16px auto;
}
.container {
width: 100%;
height: 220px;
overflow: hidden;
position: relative;
}
ul {
list-style: none;
margin: 0;
padding: 0;
height: 100%;
display: flex;
transition: transform .3s;
}
li {
height: 100%;
min-width: 100%;
}
li img {
width: 100%;
height: 100%;
object-fit: cover;
}
#prev,
#next {
position: absolute;
top: 50%;
transform: translateY(-50%);
border: none;
background: rgba(0, 0, 0, .8);
color: #fff;
font-size: 24px;
padding: 0 8px 4px;
cursor: pointer;
}
#prev:hover,
#next:hover {
opacity: .8;
}
#prev {
left: 0;
}
#next {
right: 0;
}
.hidden {
display: none;
}
nav {
margin-top: 16px;
text-align: center;
}
nav button+button {
margin-left: 8px;
}
nav button {
border: none;
width: 16px;
height: 16px;
background: #ddd;
border-radius: 50%;
cursor: pointer;
}
nav .current {
background: #999;
}