将下列代码复制到网页的Head和Body标记中间

<script language="JavaScript">

nereidFadeObjects = new Object();
nereidFadeTimers = new Object();
function nereidFade(object, destOp, rate, delta){
if (!document.all)
return
    if (object != "[object]"){  //do this so I can take a string too
        setTimeout("nereidFade("+object+","+destOp+","+rate+","+delta+")",0);
        return;
    }
    clearTimeout(nereidFadeTimers[object.sourceIndex]);
    diff = destOp-object.filters.alpha.opacity;
    direction = 1;
    if (object.filters.alpha.opacity > destOp){
        direction = -1;
    }
    delta=Math.min(direction*diff,delta);
    object.filters.alpha.opacity+=direction*delta;
    if (object.filters.alpha.opacity != destOp){
        nereidFadeObjects[object.sourceIndex]=object;
        nereidFadeTimers[object.sourceIndex]=setTimeout("nereidFade(nereidFadeObjects["+object.sourceIndex+"],"+destOp+","+rate+","+delta+")",rate);
    }
}

</script>

将下列代码放置到希望产生变化的图片标记中（<img>）

onMouseOut=nereidFade(this,50,10,5) onMouseOver=nereidFade(this,100,10,5)  style="FILTER: alpha(opacity=55)"