var marquee = function(root, row1, row2, style){
	this.m_root = document.getElementById(root);
	this.m_row1 = document.getElementById(row1);
	this.m_row2 = document.getElementById(row2);
	this.m_style = style;
 
	this.m_root.style.overflow = "hidden";
	if (this.m_style == 0){
		if (this.m_row1.offsetHeight >= this.m_root.offsetHeight-2){
			this.m_row2.innerHTML = this.m_row1.innerHTML;
		}
	}
	else{
		if (this.m_row1.offsetWidth >= this.m_root.offsetWidth-2){
			this.m_row2.innerHTML = this.m_row1.innerHTML;
		}
	}
}

marquee.prototype.scrolls = function(){
	switch(this.m_style){
	case 0:  //向上滚动
		if(this.m_row2.offsetHeight - this.m_root.scrollTop <=0){
		this.m_root.scrollTop -= this.m_row1.offsetHeight;
		}else{
		this.m_root.scrollTop++;
		}
		break;
  
	case 1:  //向左滚动
		if(this.m_row2.offsetWidth - this.m_root.scrollLeft <=0){
		this.m_root.scrollLeft -= this.m_row1.offsetWidth;
		}else{
		this.m_root.scrollLeft++;
		}
		break;
		}
}

marquee.prototype.star = function(obj, speed){
	var fm = function(){ obj.scrolls(); }
	if (this.m_style == 0){
		if (this.m_row1.offsetHeight >= this.m_root.offsetHeight-2){
			var mt = setInterval(fm, speed);
			obj.m_root.onmouseover = function(){ clearInterval(mt); }
			obj.m_root.onmouseout = function(){ mt = setInterval(fm, speed); }
		}
	}
	else{
		if (this.m_row1.offsetWidth >= this.m_root.offsetWidth-2){
			var mt = setInterval(fm, speed);
			obj.m_root.onmouseover = function(){ clearInterval(mt); }
			obj.m_root.onmouseout = function(){ mt = setInterval(fm, speed); }
		}
	}
}