<html>
<head>
<title>键盘控制div移动，解决停顿问题</title>
<meta charset="utf-8" />
<style type="text/css">
#div1{width:100px;height:100px;background:#ff0000;position:absolute;}
</style>
<script type="text/javascript">
window.onload = function(){
var oDiv = document.getElementById("div1");
var timer = null;
var left = false;
var right = false;
var top = false;
var bottom = false;
setInterval(function(){
if(left){
oDiv.style.left = oDiv.offsetLeft-10+"px";
}else if(top){
oDiv.style.top = oDiv.offsetTop-10+"px";
}else if(right){
oDiv.style.left = oDiv.offsetLeft+10+"px";
}else if(bottom){
oDiv.style.top = oDiv.offsetTop+10+"px";
}
},50);
document.onkeydown = function(ev){
var ev = ev || event;
var keyCode = ev.keyCode;
switch(keyCode){
case 37: left = true;break;
case 38: top = true;break;
case 39: right = true;break;
case 40: bottom = true;break;
}
}
document.onkeyup = function(ev){
var ev = ev || event;
var keyCode = ev.keyCode;
switch(keyCode){
case 37: left = false;break;
case 38: top = false;break;
case 39: right = false;break;
case 40: bottom = false;break;
}
}
}
</script>
</head>
<body>
<div id="div1"></div>
</body>
</html>