//tab切换 最新通知--新闻
function tab(id,aId,num1,num2,nameClass){
	var dlBlock = document.getElementById(id+num1);
	var aArray = document.getElementById(aId+num1);
	for(var i=0;i<num2;i++){
		document.getElementById(id+i).style.display='none';
		document.getElementById(aId+i).className='';
		}
	
	dlBlock.style.display='block';
	aArray.className=nameClass;
	
	}