漂浮层

 1 <div id="scrollDiv">放些文字或图片</div>
 2 <script type="text/javascript">
 3   var x = 50,y = 60;
 4   var xin = true, yin = true ;
 5   var step = 1 ;
 6   var delay = 10 ;
 7   var obj=document.getElementById("scrollDiv") ;
 8
 9   function closeDiv(){
10       document.getElementById(‘scrollDiv‘).style.display=‘none‘;
11   }
12   function rollMethod() {
13       var L=T=0;
14       var R= document.body.clientWidth-obj.offsetWidth ;
15       var B = document.body.clientHeight-obj.offsetHeight ;
16       obj.style.left = x + document.body.scrollLeft ;
17       obj.style.top = y + document.body.scrollTop ;
18       x = x + step*(xin?1:-1) ;
19       if (x < L) { xin = true; x = L}
20       if (x > R){ xin = false; x = R}
21       y = y + step*(yin?1:-1)
22       if (y < T) { yin = true; y = T }
23       if (y > B) { yin = false; y = B }
24       }
25       var itl= setInterval("rollMethod()", delay) ;
26       obj.onmouseover=function(){clearInterval(itl)} ;
27       obj.onmouseout=function(){itl=setInterval("rollMethod()", delay);
28   }
29
30 </script>