Save Javascript objects in sessionStorage

Question

The solution is to stringify the object before calling setItem on the sessionStorage.

var user = {'name':'John'};
sessionStorage.setItem('user', JSON.stringify(user));
var obj = JSON.parse(sessionStorage.user);

Could you not 'stringify' your object...then use sessionStorage.setItem() to store that string representation of your object...then when you need it sessionStorage.getItem() and then use $.parseJSON() to get it back out?

Working example http://jsfiddle.net/pKXMa/

Either you can use the accessors provided by the Web Storage API or you could write a wrapper/adapter. From your stated issue with defineGetter/defineSetter is sounds like writing a wrapper/adapter is too much work for you.

I honestly don't know what to tell you. Maybe you could reevaluate your opinion of what is a "ridiculous limitation". The Web Storage API is just what it's supposed to be, a key/value store.

This is a dynamic solution which works with all value types including objects :

class Session extends Map {
  set(id, value) {
    if (typeof value === 'object') value = JSON.stringify(value);
    sessionStorage.setItem(id, value);
  }

  get(id) {
    const value = sessionStorage.getItem(id);
    try {
      return JSON.parse(value);
    } catch (e) {
      return value;
    }
  }
}

Then :

const session = new Session();

session.set('name', {first: 'Ahmed', last : 'Toumi'});
session.get('name');

Use case:

 sesssionStorage.setObj(1,{date:Date.now(),action:'save firstObject'});
 sesssionStorage.setObj(2,{date:Date.now(),action:'save 2nd object'}); 
 //Query first object
  sesssionStorage.getObj(1)
  //Retrieve date created of 2nd object
  new Date(sesssionStorage.getObj(1).date)

API

Storage.prototype.setObj = function(key, obj) {

        return this.setItem(key, JSON.stringify(obj))
    };
    
    Storage.prototype.getObj = function(key) {
        return JSON.parse(this.getItem(key))
    };

Session storage cannot support an arbitrary object because it may contain function literals (read closures) which cannot be reconstructed after a page reload.

    var user = {'name':'John'};
    sessionStorage['user'] = JSON.stringify(user);
    console.log(sessionStorage['user']);