function gundong(){

var area = document.getElementById('guanggao');

var con1 = document.getElementById('con1');

var con2 = document.getElementById('con2');

var speed = 3000;

var myScroll = setInterval('scrollUp()', speed);

area.scrollTop = 0;

function scrollUp(){

if (area.scrollTop >= con1.scrollHeight) {

area.scrollTop = 0;

}else{

con2.innerHTML = con1.innerHTML;

area.scrollTop += area.offsetHeight;

}

}

area.onmouseover = function(){

clearInterval(myScroll);

}

area.onmouseout = function(){

myScroll =setInterval('scrollUp()', speed);

}

}

然后我調(diào)用的時(shí)候出現(xiàn)scrollUp（） undefined；