html 向上滚动 不间断,不间断向上滚动

function addEventSimple(obj, evt, fn) {

if (obj.addEventListener) {

obj.addEventListener(evt, fn, false);

} else if (obj.attachEvent) {

obj.attachEvent('on' + evt, fn);

}

}

addEventSimple(window, 'load', initScrolling);

var scrollingBox;

var scrollingInterval;

var reachedBottom = false;

var bottom;

function initScrolling() {

scrollingBox = document.getElementById('xst');

scrollingBox.style.overflow = "hidden";

scrollingInterval = setInterval("scrolling()", 50);

scrollingBox.onmouseover = over;

scrollingBox.onmouseout = out;

}

function scrolling() {

var origin = scrollingBox.scrollTop++;

if (origin == scrollingBox.scrollTop) {

if (!reachedBottom) {

scrollingBox.innerHTML += scrollingBox.innerHTML;

reachedBottom = true;

bottom = origin;

} else {

scrollingBox.scrollTop = bottom;

}

}

}

function over() {

clearInterval(scrollingInterval);

}

function out() {

scrollingInterval = setInterval("scrolling()", 50);

}