function showLayer(group, id) 
{ //处理Item
	var count = 1;  
	var obj = document.getElementById(group + "_item_" + count); 
	while (obj != null) 
	{  obj.className = "panel_item"+group; 
	   count++; 
	   obj = document.getElementById(group + "_item_" + count); 
	} 
	document.getElementById(group + "_item_" + id).className = "panel_item_show"+group; 
	//处理Layer 
	count = 1; 
	obj = document.getElementById(group + "_layer_" + count); 
	while (obj != null) 
	{ 
		obj.style.display = "none"; 
		count++; 
		obj = document.getElementById(group + "_layer_" + count); 
	} 
	document.getElementById(group + "_layer_" + id).style.display = "block"; 
}