练习鼠标跟随！以及拖拽
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<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
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<script>
另外一种鼠标跟随移动（也可以制作成拖拽）
window.onload=function(){
var xmouse=0;
var ymouse=0;
var odiv=document.getElementById("time");
odiv.onmousedown=function(ev){
var ev=ev||window.event;
xmouse=ev.clientX-odiv.offsetLeft ;
ymouse=ev.clientY-odiv.offsetTop ;
document.onmousemove=function(ev){
var ev=ev||window.event;
odiv.style.left=ev.clientX-xmouse+"px";
odiv.style.top=ev.clientY-ymouse+"px";
if(odiv.style.left<=0){
odiv.style.left=0;
}
if(odiv.style.top<=0){
odiv.style.top=0;
}
}
document.onmouseup=function(ev){
var ev=ev||window.event;
document.onmousemove=null;
document.onmousedown=null;
}
}
}
</script>
<body>
<div style="position:relative; left:300px;top:300px; width: 100px;height: 100px;" id="time">老子要显示时间</div>
</body>
</html>
