function isDOM1()
{
	if (document.getElementById)
		return true;
	else
		return false;
}

function getObj(id)
{
	return document.getElementById(id);
}

function switchDisplayStyle(objID, display)
{	
	if(!isDOM1()) return;
	var obj = getObj(objID);
	if (obj.style.display=="none")
		obj.style.display = display;
	else
		obj.style.display = "none";
	}