求助js高手..
帮忙解释一下下面的js代码是什么意思,很难懂啊.
<SCRIPT language=javascript>
if(!window.attachEvent && window.addEventListener)
{
Window.prototype.attachEvent = HTMLDocument.prototype.attachEvent=
HTMLElement.prototype.attachEvent=function(en, func, cancelBubble)
{
var cb = cancelBubble ? true : false;
this.addEventListener(en.toLowerCase().substr(2), func, cb);
};
}
function scrollPosition()
{
var L, T, w=window, d=document, dd=d.documentElement;
if(w.pageXOffset) L=w.pageXOffset;
else if(dd&&dd.scrollLeft) L=dd.scrollLeft;
else if(d.body) L=d.body.scrollLeft;
if(w.pageYOffset) T=w.pageYOffset;
else if(dd&&dd.scrollTop) T=dd.scrollTop;
else if(d.body) T=d.body.scrollTop;
return { "left ": L, "top ": T};
}
function CreateWaitElement()
{
var loading = document.getElementById( 'loading ');
if (!loading)
{
var str = " <div id= 'loading ' style= 'color: #000000; \
background-color: #FFFFAF; \
padding: 0 3px; font-size: 12px; \
font-weight: bold; height: 30px; width: 160px; \
position: absolute; border: #cccccc 1px solid;\
'> 正在处理您的请求... </div> ";
var s = document.createElement( "SPAN ");
s.innerHTML = str;
loading = s.firstChild;
document.body.insertBefore(loading, document.body.firstChild);
}
return loading;
}
window.attachEvent( "onload ", function()
{
var loading = CreateWaitElement();
loading.style.display = "none ";
window.attachEvent( "onscroll ", function(e)
{
var xy = scrollPosition();
loading.style.top = (xy.top + 10) + "px ";
loading.style.left = (xy.left + document.body.offsetWidth - 200) + "px ";
});
});
function Anthem_PreCallBack() {CreateWaitElement().style.display = " "; }
function Anthem_PostCallBack() {document.getElementById( "loading ").style.display= "none ";}
</SCRIPT>
[解决办法]
attachEvent应该是对应IE，addEventListener对应的ff，两个都是在对某个元素添加事件
Attaches the specified event handler and
function to the element so that every time
the event fires, the function is called.（attachevent IE5.0+）
这莫写就是考虑了浏览器的兼容性
