console 命令行工具 X clear

console

window.onscroll=function() {
		var oDiv=document.getElementById('div1');
		var scrollTop=document.documentElement.scrollTop||document.body.scrollTop;
		//oDiv.style.top=document.documentElement.clientHeight-oDiv.offsetHeight+scrollTop+'px';
		startMove(parseInt((document.documentElement.clientHeight-oDiv.offsetHeight)/2+scrollTop));

	}
	var timer=null;
	function startMove(iTarget) {
		var oDiv=document.getElementById('div1');
		clearInterval(timer);
		timer=setInterval(function() {
			var speed;
			speed=(iTarget-oDiv.offsetTop)/7;
			speed=speed>0?Math.ceil(speed):Math.floor(speed);
		
			if(oDiv.offsetTop==iTarget)
			{
				clearInterval(timer);

			}
			else
			{   
				document.title=iTarget;//无论加不加parseInt，值都为948
			document.getElementById('text1').value=oDiv.offsetTop;//输入框里的值为947
			oDiv.style.top=oDiv.offsetTop+speed+'px';

			
		   }
			
		},30);

}

<body style="height: 2000px;">
<input id="text1" type="text" style="position: fixed; top: 0; right: 0;">
<div id="div1"></div>
	
</body>

#div1 {width: 100px; height: 150px; background: red; position: absolute; bottom: 0; right: 0;}