本例主要是网页漂浮广告代码，就是一个小框框在网页里漂浮。这个网页漂浮广告的实现也很简单，在网页中通过javascript寻找id为img1的div，然后通过js代码来实现网页内的漂浮广告。
请看html中的代码<DIV id=img1 style="Z-INDEX: 100; LEFT: 2px; WIDTH: 59px; POSITION: absolute; TOP: 43px; HEIGHT: 61px;
visibility: visible;"><a href="http://www.ijavascript.cn" target="_blank"><img src="images/pic.gif" width="80" height="80" border="0"></a></DIV>
<SCRIPT src="js/js.js"></SCRIPT>
很简单的一个div，然后调用js.js去控制这个div
看网页漂浮广告代码里js.js的代码
var xPos = 300;
var yPos = 200;
var step = 1;
var delay = 30;
var height = 0;
var Hoffset = 0;
var Woffset = 0;
var yon = 0;
var xon = 0;
var pause = true;
var interval;
img1.style.top = yPos;
function changePos()
{
width = document.body.clientWidth;
height = document.body.clientHeight;
Hoffset = img1.offsetHeight;
Woffset = img1.offsetWidth;
img1.style.left = xPos + document.body.scrollLeft;
img1.style.top = yPos + document.body.scrollTop;
if (yon)
{yPos = yPos + step;}
else
{yPos = yPos - step;}
if (yPos < 0)
{yon = 1;yPos = 0;}
if (yPos >= (height - Hoffset))
{yon = 0;yPos = (height - Hoffset);}
if (xon)
{xPos = xPos + step;}
else
{xPos = xPos - step;}
if (xPos < 0)
{xon = 1;xPos = 0;}
if (xPos >= (width - Woffset))
{xon = 0;xPos = (width - Woffset);}
}
function start()
{
img1.visibility = "visible";
interval = setInterval('changePos()', delay);
}
function pause_resume()
{
if(pause)
{
clearInterval(interval);
pause = false;}
else
{
interval = setInterval('changePos()',delay);
pause = true;
}
}
start();
仔细研究下其实也不是很复杂！
