setCookie_getCookie

    function setCookie(c_name,value,expiredays)
      {
        var exdate=new Date();
        exdate.setDate(exdate.getDate()+expiredays);
        document.cookie=c_name+ "=" +escape(value)+
        ((expiredays==null) ? "" : ";expires="+exdate.toGMTString());
      }
      function getCookie(c_name)
        {
          if (document.cookie.length>0)
            {
              c_start=document.cookie.indexOf(c_name + "=");
              if (c_start!=-1)
                { 
                  c_start=c_start + c_name.length+1; 
                  c_end=document.cookie.indexOf(";",c_start);
                  if (c_end==-1) c_end=document.cookie.length;
                    return unescape(document.cookie.substring(c_start,c_end));
                } 
            }
              return "";
        }