function showHideSort(obj,maxNum)
{
    parentObj = obj.parentNode;
	liObjs    = obj.parentNode.getElementsByTagName("dl")[0].getElementsByTagName("dd");
	if(typeof(maxNum) == "undefined")
	{
	    //最大显示数目
	    maxNum = 3;
	}
	if(obj.className == "classJs jsOpen")
	{
	    obj.className = "classJs jsClose";
	}
	else
	{
	    obj.className = "classJs jsOpen";
	}
	if(liObjs.length > maxNum)
	{
	    for(i = maxNum;i < liObjs.length;i++)
		{
		    //这里可以className
			//if(liObjs[i].className = "show") 一边的
		    if(liObjs[i].style.display == "none")
			{
			    liObjs[i].style.display = "";
			}
			else
			{
			    liObjs[i].style.display = "none";
			}
		}
	}
}