首頁 > 開發者 > JavaScript
a.scrollTop的計算；
b.滾動元素的定位值計算；
c.滾動周期設定；
代碼如下：
css部分：
複製代碼 代碼如下:
/*測試用的高度*/
body{ height:3000px;}
div,ul,li,body{margin:0; padding:0;}
/*position:absolute;用於元素的定位*/
#roll{width:50px; height:100px; background:#99CC00; position:absolute;}
Html代碼：
複製代碼 代碼如下:
<body>
<div id="roll"></div>
</body>
JS代碼：
複製代碼 代碼如下:
var roll=document.getElementById('roll'),
initX=0,
initY,
compY,
sp=15,
//可調整時間間隔，步進值不宜過大，不然IE下有點閃屏；
timeGap=5,
doc=document.documentElement,
docBody=document.body;
compY=initY=200;
roll.style.right=initX+"px";
;(function(){
var curScrollTop=(doc.scrollTop||docBody.scrollTop||0)-(doc.clientTop||docBody.clientTop||0);
//每次comP的值都不一樣；直到roll.style.top===doc.scrollTop+initY；
compY+=(curScrollTop+initY-compY)/sp;
roll.style.top=Math.ceil(compY)+"px";
setTimeout(arguments.callee,timeGap);
})();
Start building with 50+ products and up to 12 months usage for Elastic Compute Service
1 on 1 presale consultation
24/7 Technical Support 6 Free Tickets per Quarter Faster Response
Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.
A comprehensive suite of global cloud computing services to power your business
Payment Methods We Support
