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                        /前端開發(fā)
                        
                            /JavaScript
                        
                        /JS動(dòng)畫效果

為什么我的if判斷無(wú)效 ?

<!DOCTYPE?html?PUBLIC?"-//W3C//DTD?XHTML?1.0?Transitional//EN"?"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html?xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta?http-equiv="Content-Type"?content="text/html;?charset=utf-8"?/>
<title>無(wú)標(biāo)題文檔</title>
<style>
#div1??{width:?200px;?height:?200px;?background:?red;?position:?relative;?left:?-200px;?top:?0px;}
#div1?span?{width:?20px;?height:?42px;?background:?blue;?display:?block;?position:?absolute;?left:?200px;?top:?60px;?color:?#fff;?font-size:?14px;?text-align:	?center;?padding-top:?10px;}
</style>
<script>
window.onload=function(){
	var?oDiv?=?document.getElementById('div1')
	oDiv.onmouseover?=?function(){
		startMove();
	}
}
var?timer?=?null;
function?startMove(){
	var?oDiv?=?document.getElementById('div1')
	timer?=?setInterval(function(){
		if(oDiv.offsetLeft==0){
			clearInterval(timer);
		}
		else{
		oDiv.style.left?=?oDiv.offsetLeft+10+'px';?
	}
	},30)
}

</script>
</head>

<body>
<div?id="div1">
?????<span?id="share">分享</span>
</div>


</body>
</html>