if(typeof(window.localStorage) == undefined) {
   // use cookie
   window.localStorage = {
       cookieName: 'localStorageCookie',
       length: 0,
       getItem: function(key) {
            key = this.cookieName + '.' + key;
            var equalName = key + '=';
            var cookie = document.cookie.split(';');
            for(var i = 0; i < cookie.length; i++)
            {
                var c = cookie[i];
                while(c.charAt(0) == ' ')
                {
                    c = c.substring(1, c.length);
                }
                if(c.indexOf(equalName) == 0) {
                    return c.substring(equalName.length, c.length);
                }
            }

            return null;
       },
       setItem: function(key, value) {
           this.__setCookie(key, value);
           this.length++;
       },
       removeItem: function(key) {
           this.__setCookie(key, '', -1);
           this.length--;
       },
       clear: function() {
           var cookie = document.cookie.split(';');
           for(var i = 0; i < cookie.length; i++)
           {
               var c = cookie[i].replace(/^\s+/, '');
               if(c.indexOf(this.cookieName) == 0) {
                   c = c.replace(this.cookieName + '.', '').split('=');
                   this.removeItem(c[0]);
               }

               this.length = 0;
           }
       },
       __setCookie: function(key, value, expires) {
           key = this.cookieName + '.' + key;
           if(expires == undefined) {
               var date = new Date();
               date.setTime(date.getTime() + (1000 * 60 * 60 * 24 * 7)); // ms * sec * min * hours * days
               expires = date.toGMTString();
           } else if(expires == -1) {
               var date = new Date();
               expires = date.toGMTString();
           }
           document.cookie = key + '=' + value + '; expires=' + expires + '; path=/';
       }
   }
}