Hacking and Gonzo, a publication by Amir Salihefendic since 2000

Storing arbitrary objects in HTML5's localStorage

To store arbitrary objects in HTML5's localStorage you just JSON encode them (as you can only store strings).

Here is my CoffeeScript helper extension:

if window.Storage and window.JSON
    window.$storage = (key) ->
        set: (value) ->
            localStorage.setItem(key, JSON.stringify(value))
        get: ->
            item = localStorage.getItem(key)
            JSON.parse(item) if item

Usage:

$storage("my_object").set({"meaning": 42})
$storage("my_object").get() //Equals to {"meaning": 42}

JavaScript version:

if(window.Storage && window.JSON) {
  window.$storage = function(key) {
    return {
      set: function(value) {
        return localStorage.setItem(key, JSON.stringify(value));
      },

      get: function() {
        var item = localStorage.getItem(key);
        if (item) {
          return JSON.parse(item);
        }
      }
    };
  };
}

28. Jun 2011 • Code · Code improvement · JavaScript · node.js