function navlihover(){
	var navlihover=document.getElementById("subul1");
	navlihover.style.display="block";
	}
function navli(){
	var navlihover=document.getElementById("subul1");
	navlihover.style.display="none";
	}
function navlihover1(){
	var navlihover=document.getElementById("subul2");
	navlihover.style.display="block";
	}
function navli1(){
	var navlihover=document.getElementById("subul2");
	navlihover.style.display="none";
	}
function navlihover2(){
	var navlihover=document.getElementById("subul3");
	navlihover.style.display="block";
	}
function navli2(){
	var navlihover=document.getElementById("subul3");
	navlihover.style.display="none";
	}
function so()
{
    var o=document.getElementById("kw");
    if(o!=null)
    {
        if(o.value=="" || o.value=="输入搜索内容")
        {
            alert("请输入搜索内容");
            o.focus();
            return false;
        }
    }
}