/**
 * @author Administrator
 */
function fanye(divId,pChange){
	var currDiv,currPage;
	var currHeight,currTop,factHeight;

	if (!document.getElementById(divId)){
		return;
	}else{
		currDiv = document.getElementById(divId);
	}
	if(pChange!="up" && pChange!="down"){
		return;
	}
	factHeight = parseInt(currDiv.offsetHeight);
	//alert("offsetHeight="+factHeight);
	currTop = parseInt(currDiv.style.top);
	currHeight = parseInt(currDiv.getAttribute("title"));
	//alert(currHeight);
	if(pChange == "up"){
		if(currTop<0){
			currTop = currTop+currHeight;
		}
	}else if(pChange == "down"){
		if((-currTop)<(factHeight-currHeight)){
			currTop = currTop-currHeight;
		}
	}
	currDiv.style.top = currTop+"px";
}