javascript localstorage toDo list

javascriptLocalstorageToDo.js

/****
 Sten Hougaard, @netsi1964, Localstorage items
 Ver 0.98, not fully tested
 Please note: Do not support storing of objects with functions

 Added option to parse key (when using more than one localstorage)
 Changed names from toDos to items, more generic
****/
var items;
if (typeof localStorage === 'undefined' ) {
  alert('Your browser does not support HTML5 localStorage. Try upgrading.');
} else {
  try {
    items = {
      key: 'items'+(new Date()-new Date(1964,8,23)),
      getItems: function(key) {
        key = (typeof key!=='undefined') ? key : this.key;
        var _temp = localStorage.getItem(key);
        var current = (_temp===null) ? [] : JSON.parse(_temp);
        localStorage.setItem(key, JSON.stringify(current));
        return current;
      },
      add: function(oItem, key) {
        key = (typeof key!=='undefined') ? key : this.key;
        var items = this.getItems(key);
        items[items.length] = JSON.stringify(oItem);
        return localStorage.setItem(key, JSON.stringify(items));
      },
      set: function(index, value, key) {
        key = (typeof key!=='undefined') ? key : this.key;
        var items = JSON.parse(this.getItems());
        items[index] = value;
        localStorage.setItem(key, JSON.stringify(items));
        return items;
      },
      get: function(index, key) {
        key = (typeof key!=='undefined') ? key : this.key;
        var items = this.getItems();
        return JSON.parse(items[index]);
      },
      remove: function(index, key) {
        key = (typeof key!=='undefined') ? key : this.key;
        var items = this.getItems();
        var removed = items.splice(index, 1);
        localStorage.setItem(key, JSON.stringify(items));
        return removed;
      }
    }
  } catch (e) {
    if (e == QUOTA_EXCEEDED_ERR) {
      alert('Quota exceeded!'); //data wasn’t successfully saved due to quota exceed so throw an error
    }
  }
}