<!DOCTYPE html>
<html>
<head>
<title>作业</title>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<style type="text/css">
div{
width: 100px;
height: 100px;
border:1px solid black;
position: absolute;
left: 300px;
top: 200px;
}
</style>
<script type="text/javascript">
window.onload=function(){
window.setInterval("show()", 500);
}
function show(){
var left=Math.random()*1000;
var top=Math.random()*500;
document.getElementById("d").style.left=left+"px";
document.getElementById("d").style.top=top+"px";
}
</script>
</head>
<body>
<div id="d">
<img src="1.jpg" width="100" height="100"/>
</div>
</body>
</html>
