注册鼠标滚轮事件

var scrollFunc = function(e){
e=e || window.event;
if(e.wheelDelta>0){
//上滚
}else if(e.wheelDelta<0){
//下滚
}

}


/*注册事件*/
if(document.addEventListener){
document.addEventListener('DOMMouseScroll',scrollFunc,false);//火狐
}//W3C
window.onmousewheel=document.onmousewheel=scrollFunc;//IE/Opera/Chrome