<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<style>
* {
margin: 0;
padding: 0
}
#box {
height: 140px;
400px;
border: 1px solid #cccccc;
color: hotpink;
overflow: hidden;
margin: 50px auto;
text-align: center;
}
</style>
</head>
<body>
<div id="box">
<ul id="ul1">
<li>1111111111111111111111</li>
<li>2222222222222222222222</li>
<li>3333333333333333333333</li>
<li>4444444444444444444444</li>
<li>5555555555555555555555</li>
<li>6666666666666666666666</li>
<li>7777777777777777777777</li>
<li>8888888888888888888888</li>
<li>9999999999999999999999</li>
</ul>
<ul id="ul2"></ul>
</div>
<script>
window.onload = roll(50);
// 传入的 t 为滚动快慢的时间
function roll(t) {
console.log(1);
let ul1 = document.getElementById("ul1");
let ul2 = document.getElementById("ul2");
let box = document.getElementById("box");
ul2.innerHTML = ul1.innerHTML; //这一句很关键，此效果的实现是通过ul1和ul2之间的相互切换实现的无缝滚动效果，如果这一句没有将ul1中的内容追加到ul2中，将不会实现元素的循环滚动
// 初始化滚动高度
box.scrollTop = 0;
let timer = setInterval(rollStart, t);
box.onmouseover = function () {
clearInterval(timer)
}
box.onmouseout = function () {
timer = setInterval(rollStart, t);
}
}
function rollStart() {
if (box.scrollTop >= ul1.scrollHeight) {
box.scrollTop = 0;
} else {
box.scrollTop++;
}
}
</script>
</body>
</html>
实现的效果如下所示：
