<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1">
<title></title>
<style type="text/css">
#sls-silder {
width: 1000px;
height: 50px;
border-radius: 5px;
background-color: #eee;
position: relative;
}
#sls-silder-btn {
position: absolute;
transform: translate(0, -50%);
left: 0;
top: 50%;
height: 30px;
width: 30px;
border-radius: 50%;
background-color: greenyellow;
cursor: pointer;
}
</style>
</head>
<body>
<div id="sls-silder">
<div id="sls-silder-btn"></div>
</div>
<script type="text/javascript">
let silder = document.getElementById(‘sls-silder‘);
let btn = document.getElementById(‘sls-silder-btn‘);
let wapperWidth = 1000; //父容器的宽度
let btnWidth = 30; //按钮宽度
let wapperPadding = 0 ; //父容器的内边距
let go = false;
let numb = 0;
btn.onmousedown = function(res) {
go = true;
}
btn.onmouseup = function(res) {
go = false
};
silder.addEventListener(‘mousemove‘, res => {
if (go && res.pageX < wapperWidth && res.pageX > btnWidth) {
numb = res.pageX - btnWidth;
console.log(res.pageX)
btn.style = `left:${numb}px`;
}
})
</script>
</body>
</html>
原文：https://www.cnblogs.com/ooo51o/p/14783739.html