js-網站廣告圖片漂浮

<div id="codefans_net" style="position:absolute">	

	<a href="#" target="_blank">

		<img src="images/banner.png" width='400px' border="0">

	</a>

</div>	

<script> 
var x = 50,y = 60 
var xin = true, yin = true 
var step = 1 
var delay = 10 
var obj=document.getElementById("codefans_net") 
function float() { 
var L=T=0
var R= document.body.clientWidth-obj.offsetWidth 
var B = document.body.clientHeight-obj.offsetHeight 
obj.style.left = x + document.body.scrollLeft 
obj.style.top = y + document.body.scrollTop 
x = x + step*(xin?1:-1) 
if (x < L) { xin = true; x = L} 
if (x > R){ xin = false; x = R} 
y = y + step*(yin?1:-1) 
if (y < T) { yin = true; y = T } 
if (y > B) { yin = false; y = B } 
} 
var itl= setInterval("float()", delay) 
obj.onmouseover=function(){clearInterval(itl)} 
obj.onmouseout=function(){itl=setInterval("float()", delay)} 
</script>

//在寫好的頁面上，放這段代碼，圖片怎麼都不動。

//後面改成jquery，好使了。

//宣傳圖片漂浮
    var x = 50,y = 60;
	var xin = true, yin = true;
	var step = 1;
	var delay = 10;
	var obj=$('#codefans_net');
	function float() {
		var L=T=0
		var R= $(window).width()-obj.outerWidth();
		var B = $(window).height()-obj.outerHeight();
		obj.css('left',x+$('body').scrollLeft());
		obj.css('top',y+$('body').scrollTop());
		x = x + step*(xin?1:-1)
		if (x < L){
			xin = true;
			x = L
		}
		if (x > R){
			xin = false;
			x = R
		}
		y = y + step*(yin?1:-1)
		if (y < T) {
			yin = true;
			y = T;
		}
		if (y > B){
			yin = false;
			y = B
		}
	}
	var itl= setInterval("float()", delay)
	obj.mouseover(function(){
		clearInterval(itl);
	});
	obj.mouseout(function(){
		itl=setInterval("float()", delay);
	});
	//----------漂浮完