The example in this article describes how JavaScript implements scrolling and floating ad code with a buffering effect on the screen. Share it with everyone for your reference, the details are as follows:
Here is a demonstration of JavaScript code that always scrolls with the screen. It is widely used in China. Especially some webmasters who like floating ads often use this code as floating ads. In fact, the original intention of this effect is Write a menu that scrolls with the screen so that visitors can control the navigation of the website anytime and anywhere.
The screenshot of the running effect is as follows:
The online demo address is as follows:
http://demo.jb51.net/js/2015/js-hc-style-scroll-adv-codes/
The specific code is as follows:
<html>
<head>
<title>随屏滚动</title>
<style type="text/css">
*{padding:0;margin:0;}
html{height:100%;}
body{height:200%;}
.box{position:absolute;width:100px;height:100px;background:#ccc}
</style>
</head>
<body>
<div class="box" id="box1" style="top:0;left:0;">AD1</div>
<div class="box" id="box2" style="top:0;right:0;">AD2</div>
</body>
<script type="text/javascript">
var id=function(o){return document.getElementById(o)}
var scroll=function (o){
var space=id(o).offsetTop;
id(o).style.top=space+'px';
void function(){
var goTo = 0;
var roll=setInterval(function(){
var height =document.documentElement.scrollTop+document.body.scrollTop+space;
var top = parseInt(id(o).style.top);
if(height!= top){
goTo = height-parseInt((height - top)*0.9);
id(o).style.top=goTo+'px';
}
//else{if(roll) clearInterval(roll);}
},50);
}()
}
scroll('box1');
scroll('box2');
</script>
</html>I hope this article will be helpful to everyone in JavaScript programming.
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