本文实例为大家分享了js上下滑动效果的具体代码，供大家参考，具体内容如下
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box{
width: 512px;
height: 400px;
margin:100px auto;
overflow: hidden;
position: relative;
border: 1px solid red;
}
.box img{
position: absolute;
left: 0;
top: 0;
}
.box div{
width: 512px;
height: 200px;
position: absolute;
left: 0;
}
.up{
top:0;
}
.down{
top: 200px;
}
</style>
<script>
window.onload = function(){
function $(id){ return document.getElementById(id);}
var num = 0;
var timer;
var timer1;
$("picup").onmouseover = function(){ //往下走
timer = setInterval(function(){
if(num>=0){
clearInterval(timer);
}else{
num+=3;
$("pic").style.top = num +"px";
}
},10);
}
$("picup").onmouseleave = function(){
clearInterval(timer);
}
$("picdown").onmouseover = function(){ //往上走
timer1 = setInterval(function(){
if(num <= -1070){
clearInterval(timer1);
}else{
num-=3;
$("pic").style.top = num +"px";
}
},30);
}
$("picdown").onmouseleave = function(){
clearInterval(timer1);
}
}
</script>
</head>
<body>
<div class="box">
<img src="mi.png" alt="" id="pic">
<div class="up" id="picup"></div>
<div class="down" id="picdown"></div>
</div>
</body>
</html>