JavaScript Lightbox
介绍如何使用 HTML、JavaScript 与 CSS 来创建 Lightbox，类似相册预览功能。
HTML 代码：
<!-- 图片改为你的图片地址 -->
<h2 style="text-align:center">Lightbox</h2>
<div class="row">
<div class="column">
<img decoding="async" src="http://static.runoob.com/images/demo/demo1.jpg" style="width:100%" onclick="openModal();currentSlide(1)" class="hover-shadow cursor">
</div>
<div class="column">
<img decoding="async" src="http://static.runoob.com/images/demo/demo2.jpg" style="width:100%" onclick="openModal();currentSlide(2)" class="hover-shadow cursor">
</div>
<div class="column">
<img decoding="async" src="http://static.runoob.com/images/demo/demo3.jpg" style="width:100%" onclick="openModal();currentSlide(3)" class="hover-shadow cursor">
</div>
<div class="column">
<img decoding="async" src="http://static.runoob.com/images/demo/demo4.jpg" style="width:100%" onclick="openModal();currentSlide(4)" class="hover-shadow cursor">
</div>
</div>
<div id="myModal" class="modal">
<span class="close cursor" onclick="closeModal()">×</span>
<div class="modal-content">
<div class="mySlides">
<div class="numbertext">1 / 4</div>
<img decoding="async" src="http://static.runoob.com/images/demo/demo1.jpg" style="width:100%">
</div>
<div class="mySlides">
<div class="numbertext">2 / 4</div>
<img decoding="async" src="http://static.runoob.com/images/demo/demo2.jpg" style="width:100%">
</div>
<div class="mySlides">
<div class="numbertext">3 / 4</div>
<img decoding="async" src="http://static.runoob.com/images/demo/demo3.jpg" style="width:100%">
</div>
<div class="mySlides">
<div class="numbertext">4 / 4</div>
<img decoding="async" src="http://static.runoob.com/images/demo/demo4.jpg" style="width:100%">
</div>
<a class="prev" onclick="plusSlides(-1)">❮</a>
<a class="next" onclick="plusSlides(1)">❯</a>
<div class="caption-container">
<p id="caption"></p>
</div>
<div class="column">
<img decoding="async" class="demo cursor" src="http://static.runoob.com/images/demo/demo1.jpg" style="width:100%" onclick="currentSlide(1)" alt="Nature and sunrise">
</div>
<div class="column">
<img decoding="async" class="demo cursor" src="http://static.runoob.com/images/demo/demo2.jpg" style="width:100%" onclick="currentSlide(2)" alt="Trolltunga, Norway">
</div>
<div class="column">
<img decoding="async" class="demo cursor" src="http://static.runoob.com/images/demo/demo3.jpg" style="width:100%" onclick="currentSlide(3)" alt="Mountains and fjords">
</div>
<div class="column">
<img decoding="async" class="demo cursor" src="http://static.runoob.com/images/demo/demo4.jpg" style="width:100%" onclick="currentSlide(4)" alt="Northern Lights">
</div>
</div>
</div>
CSS 代码：
body {
font-family: Verdana, sans-serif;
margin: 0;
}
* {
box-sizing: border-box;
}
.row > .column {
padding: 0 8px;
}
.row:after {
content: "";
display: table;
clear: both;
}
.column {
float: left;
width: 25%;
}
/* 弹窗背景 */
.modal {
display: none;
position: fixed;
z-index: 1;
padding-top: 100px;
left: 0;
top: 0;
width: 100%;
height: 100%;
overflow: auto;
background-color: black;
}
/* 弹窗内容 */
.modal-content {
position: relative;
background-color: #fefefe;
margin: auto;
padding: 0;
width: 90%;
max-width: 1200px;
}
/* 关闭按钮 */
.close {
color: white;
position: absolute;
top: 10px;
right: 25px;
font-size: 35px;
font-weight: bold;
}
.close:hover,
.close:focus {
color: #999;
text-decoration: none;
cursor: pointer;
}
.mySlides {
display: none;
}
.cursor {
cursor: pointer
}
/* 上一页 & 下一页 按钮 */
.prev,
.next {
cursor: pointer;
position: absolute;
top: 50%;
width: auto;
padding: 16px;
margin-top: -50px;
color: white;
font-weight: bold;
font-size: 20px;
transition: 0.6s ease;
border-radius: 0 3px 3px 0;
user-select: none;
-webkit-user-select: none;
}
/* 定位下一页按钮到右侧 */
.next {
right: 0;
border-radius: 3px 0 0 3px;
}
/* 鼠标移动上去修改背景色为黑色 */
.prev:hover,
.next:hover {
background-color: rgba(0, 0, 0, 0.8);
}
/* 页数(1/3 etc) */
.numbertext {
color: #f2f2f2;
font-size: 12px;
padding: 8px 12px;
position: absolute;
top: 0;
}
img {
margin-bottom: -4px;
}
.caption-container {
text-align: center;
background-color: black;
padding: 2px 16px;
color: white;
}
.demo {
opacity: 0.6;
}
.active,
.demo:hover {
opacity: 1;
}
img.hover-shadow {
transition: 0.3s
}
.hover-shadow:hover {
box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19)
}
JavaScript 代码：
function openModal() {
document.getElementById('myModal').style.display = "block";
}
function closeModal() {
document.getElementById('myModal').style.display = "none";
}
var slideIndex = 1;
showSlides(slideIndex);
function plusSlides(n) {
showSlides(slideIndex += n);
}
function currentSlide(n) {
showSlides(slideIndex = n);
}
function showSlides(n) {
var i;
var slides = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("demo");
var captionText = document.getElementById("caption");
if (n > slides.length) {slideIndex = 1}
if (n < 1) {slideIndex = slides.length}
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
}
for (i = 0; i < dots.length; i++) {
dots[i].className = dots[i].className.replace(" active", "");
}
slides[slideIndex-1].style.display = "block";
dots[slideIndex-1].className += " active";
captionText.innerHTML = dots[slideIndex-1].alt;
}
