在下面的脚本中，代码在有滑动条的情况下工作，但当页面上的滑动条数量多于一个时，下一个滑动条就不起作用了。
当我们在页面上有多个滑动条时，如何更改此脚本，以便每个滑动条"可拖拽功能单独工作，不重叠?
需要做哪些修改才能使这段代码"可拖动特性">为每个滑块单独工作?
如何使用">querySelectorAll";和";forEach";
?
const slider = document.querySelector('.items');
let isDown = false;
let startX;
let scrollLeft;
slider.addEventListener('mousedown', (e) => {
isDown = true;
slider.classList.add('active');
startX = e.pageX - slider.offsetLeft;
scrollLeft = slider.scrollLeft;
});
slider.addEventListener('mouseleave', () => {
isDown = false;
slider.classList.remove('active');
});
slider.addEventListener('mouseup', () => {
isDown = false;
slider.classList.remove('active');
});
slider.addEventListener('mousemove', (e) => {
if (!isDown) return;
e.preventDefault();
const x = e.pageX - slider.offsetLeft;
const walk = (x - startX) * 3; //scroll-fast
slider.scrollLeft = scrollLeft - walk;
});.items,
.items_1 {
position: relative;
width: 90%;
background: green;
overflow-x: scroll;
overflow-y: hidden;
white-space: nowrap;
transition: all 0.2s;
transform: scale(0.98);
will-change: transform;
user-select: none;
cursor: pointer;
margin: 2rem auto;
border: 3px solid violet;
}
.item {
display: inline-block;
background: red;
min-height: 50px;
min-width: 150px;
margin: .5rem;
}<!DOCTYPE html>
<html lang="en">
<head>
<title>slider</title>
<link rel="stylesheet" href="./style.css">
</head>
<body>
<div class="items">
<div class="item"></div>
<div class="item"></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
</div>
<div class="items">
<div class="item"></div>
<div class="item"></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
</div>
<div class="items">
<div class="item"></div>
<div class="item"></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
</div>
<script src="./script.js"></script>
</body>
</html>如何使用"querySelectorAll";和";forEach";
?
只需将声明状态变量并将事件处理程序附加到一个滑动条的代码放入这样的循环中:
const sliders = document.querySelectorAll('.items');
for (const slider of sliders) {
let isDown = false;
let startX;
let scrollLeft;
slider.addEventListener('mousedown', (e) => {
isDown = true;
slider.classList.add('active');
startX = e.pageX - slider.offsetLeft;
scrollLeft = slider.scrollLeft;
});
slider.addEventListener('mouseleave', () => {
isDown = false;
slider.classList.remove('active');
});
slider.addEventListener('mouseup', () => {
isDown = false;
slider.classList.remove('active');
});
slider.addEventListener('mousemove', (e) => {
if (!isDown) return;
e.preventDefault();
const x = e.pageX - slider.offsetLeft;
const walk = (x - startX) * 3; //scroll-fast
slider.scrollLeft = scrollLeft - walk;
});
}.items {
position: relative;
width: 90%;
background: green;
overflow-x: scroll;
overflow-y: hidden;
white-space: nowrap;
transition: all 0.2s;
transform: scale(0.98);
will-change: transform;
user-select: none;
cursor: pointer;
margin: 2rem auto;
border: 3px solid violet;
}
.items.active {
border-color: blue;
}
.item {
display: inline-block;
background: red;
min-height: 50px;
min-width: 150px;
margin: .5rem;
}<!DOCTYPE html>
<html lang="en">
<head>
<title>slider</title>
<link rel="stylesheet" href="./style.css">
</head>
<body>
<div class="items">
<div class="item"></div>
<div class="item"></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
</div>
<div class="items">
<div class="item"></div>
<div class="item"></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
</div>
<div class="items">
<div class="item"></div>
<div class="item"></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
<div class="item "></div>
</div>
<script src="./script.js"></script>
</body>
</html>