//javascript cookie类
function jsCookie(){   
  
    var COOKIE_LIFE ={year:31536000,month:2592000,week:604800,   
  
                      day:86400,hour:3600,browser:0}   
  
       
  
    this.expires = 'browser';   
  
    this.path = null;   
  
    this.domain = null;   
  
    this.secure = null;   
  
       
  
    this.get=function(fieldName){       
  
        var regexp = window.eval("/"+fieldName+"=([\\w%,]+)(|;)/");   
  
        var result = document.cookie.match(regexp);   
  
        return (result?unescape(result[1]):null);   
  
    }       
  
    this.set=function(fieldName,fieldValue){   
  
        var cookie_list;   
  
        cookie_list = fieldName+"="+escape(fieldValue);           
  
        cookie_list += expires_param(this.expires);   
  
        cookie_list += path_param(this.path);   
  
        cookie_list += domain_param(this.domain);   
  
        cookie_list += secure_param(this.secure);   
  
        document.cookie = cookie_list;   
  
    }   
  
    function expires_param(expires){   
  
        var tm=0;   
  
        if(typeof(expires)=='string'){   
  
            if(!COOKIE_LIFE[expires]) return "";       
  
            tm = COOKIE_LIFE[expires]*1000;           
  
        }else if(typeof(expires)=='number'){               
  
            tm = expires*1000;   
  
        }else{return "";}   
  
        expires = ";expires="+new Date(new Date().getTime()+ tm).toUTCString();   
  
        return expires;   
  
    }   
  
    function path_param(path){   
  
        if(!path) return "";   
  
        return (";path="+path);   
  
    }   
  
    function domain_param(domain){   
  
        if(!domain) return "";   
  
        return (";domain="+domain);   
  
    }   
  
    function secure_param(secure){   
  
        if(secure!='secure') return "";       
  
        return ";secure";   
  
    }   
  
}  

//使用方法
//ck = new jsCookie();
  
//ck.expires = 'browser';   
  
//ck.path='/';  //可以不写 
  
//ck.domain='.xxx.com';  //可以不写  
  
//ck.secure = 'secure';   //可以不写 
  
//ck.set("abc","123456");   
  
//alert(ck.get("abc"));   
function NavMenu(n)
{
    ck = new jsCookie();  
    ck.expires = 'browser';
    ck.set("menuid",n);
    var menuarry=document.getElementById("TopNav").getElementsByTagName("li");
    var menuEng=document.getElementById("NavEn").getElementsByTagName("li");
    for(var i=0;i<menuarry.length;i++)
    {
        if(i==0)
        {
            menuarry[i].className="menu_1";
        }
        else
        {
            menuarry[i].className="menu_2";
        }
    }
    for(var i=0;i<menuarry.length;i++)
    {
       menuEng[i].className="tp2";
    }
    menuEng[n-1].className="tp1";
    if( n == 1)
    {
      menuarry[n-1].className="menu_expanded1";
    }
    else{
      menuarry[n-1].className="menu_expanded2";
    }    
}
window.onload = function(){ 
   ck = new jsCookie();  
   ck.expires = 'browser';
   if(ck.get("menuid")!= null)
   {
       NavMenu(ck.get("menuid"));
   }
   else
   {
     NavMenu(1);
   }
}