个人觉得可通过 scrollIntoView()函数实现网页返回顶部的功能;
<html>
<head>
<title>HTML5_ScrollInToView方法</title>
<meta charset="utf-8">
<style>
#begin{
width: 100%;
height: 100%;
background: pink;
}
#box{
width: 100%;
height: 800px;
background: #000;
border:1px solid black;
}
</style>
</head>
<body>
<input id="btn2" type="button" value="false" onclick="falseScrollIntroview()">
<div id="begin">
</div>
<div id="box"></div>
<input id="btn1" type="button" value="ture" onclick="trueScrollIntroview()">
<script>
var btn1=document.getElementById("btn1");
var btn2=document.getElementById("btn2");
var box=document.getElementById("box");
var begin=document.getElementById("begin");
function trueScrollIntroview() {
begin.scrollIntoView(true);
}
function falseScrollIntroview() {
box.scrollIntoView(false);
}
// var box=document.querySelector("#box");
// box.style.height="300px";
</script>
</body>
</html>