键值控制
键值监听
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>onkeydown</title>
</head>
<body>
<div id="div" style="width:100px;height: 100px;background: blue;position:absolute;top:0;left:0;"></div>
</body>
<script type="text/javascript">
var oDiv = document.getElementById('div');
var timer = null ;
var iCode = {};
document.onkeydown = function(ev){
var ev = ev || window.event ;
iCode[ev.keyCode]= true;//获取键值。
console.log(iCode);//利用JSON存储
}
document.onkeyup = function(ev){
var ev = ev || window.event ;
iCode[ev.keyCode] = false ;
}
timer = setInterval(function(){
if(iCode[37]){//左键
oDiv.style.left = oDiv.offsetLeft - 10 + 'px';
}if(iCode[38]){ //上键
oDiv.style.top = oDiv.offsetTop - 10 + 'px';
}if(iCode[39]){//右键
oDiv.style.left = oDiv.offsetLeft + 10 + 'px';
}if(iCode[40]){ //下键
oDiv.style.top = oDiv.offsetTop+ 10 + 'px';
}
},20);
</script>
</html>
