1 <a class="totop" id="to_top"></a>
2
3 <script>
4 /*回到顶部的功能*/
5 window.onload = function(){
6 var oTop = document.getElementById("to_top");
7 var screenh = document.documentElement.clientHeight || document.body.clientHeight;
8 oTop.style.top = screenh - oTop.offsetHeight + "px";
9 window.onscroll = function(){
10 var scrolltop = document.documentElement.scrollTop || document.body.scrollTop;
11 oTop.style.top = screenh - oTop.offsetHeight + scrolltop +"px";
12 }
13 oTop.onclick = function(){
14 document.documentElement.scrollTop = document.body.scrollTop =0;
15 }
16 }
17 </script>
