这么写为什么不行
<script type=text/javascript>
window.onload=function(){
var bo1=document.getElementById(box);
bo1.onmouseover=function(){
boc(1);
}
bo1.onmouseout=function(){
boc(0.3);}
}
function boc(ita)
{
var bo1=document.getElementById(box);
bo1.style.opacity=ita;
}
</script>
