js无缝滚动-向上滚动[转载]

 1<style>
 2a {}{font-size:9pt;color:#333;text-decoration:none;}
 3a:hover {}{color:#111;text-decoration:underline;}
 4</style>
 5
 6<div id="marquees">
 7  <a href="#">你可曾有过无数的梦想</a><br><br>
 8  <a href="#">却在时光的流逝里幻灭</a><br><br>
 9  <a href="#">你可曾对未来期待憧憬</a><br><br>
10  <a href="#">却在成长的岁月中迷失</a><br><br>
11</div> 
12<script language="JavaScript">
13marqueesHeight=200;
14stopscroll=false;
15with(marquees){
16  style.width=0;
17  style.height=marqueesHeight;
18  style.overflowX="visible";
19  style.overflowY="hidden";
20  noWrap=true;
21  onmouseover=new Function("stopscroll=true");
22  onmouseout=new Function("stopscroll=false");
23}
24document.write('<div id="templayer" style="position:absolute;z-index:1;visibility:hidden"></div>');
25
26preTop=0; currentTop=0; 
27
28function init(){
29  templayer.innerHTML="";
30  while(templayer.offsetHeight<marqueesHeight){
31    templayer.innerHTML+=marquees.innerHTML;
32  }
33  marquees.innerHTML=templayer.innerHTML+templayer.innerHTML;
34  setInterval("scrollUp()",50);
35}
36document.body.onload=init;
37
38function scrollUp(){
39  if(stopscroll==true) return;
40  preTop=marquees.scrollTop;
41  marquees.scrollTop+=1;
42  if(preTop==marquees.scrollTop){
43    marquees.scrollTop=templayer.offsetHeight-marqueesHeight;
44    marquees.scrollTop+=1;
45  }
46}
47</script> 
48