![mousewheel 模拟滚动]( "mousewheel 模拟滚动")
div{
box-sizing:border-box;
}
.father{
width:500px;
height:400px;
margin:auto;
margin-top: 50px;
border: 1px solid red;
overflow: hidden;
position: relative;
}
.child{
width:60%;
height: 1210px;
border: 1px solid green;
margin:auto;
position: absolute;
left:100px;
}
function load(){
window.child=document.getElementById('child');
window.father=child.parentNode;
father.addEventListener('mousewheel',function(e){
// father.addEventListener('scroll',function(e){
e.preventDefault();
e.stopPropagation();
move(e.deltaY*-1);
})
}
function move(offset)
{
var top = child.style.top;
if(top==='')
{
top=0;
offset= offset/1 + top/1;
}
else
{
top=top.replace('px','');
offset= offset/1 + top/1;
}
var moved=Math.abs(offset) +father.offsetHeight;
if(moved>child.offsetHeight && offset<0)
{
child.style.top = -1*(child.offsetHeight-father.offsetHeight+6) +'px';
return;
}
if(offset>0)
{
child.style.top='0px';
return;
}
child.style.top=(offset) +'px';
}
<body onload="load()">
<div class="father">
<div class="child" id="child">
</div>
</div>
