Question

I just learned about jquery’s .makeArray and I am trying to use JSON.stringify to store the array in localStorage but I am having unexpected results.

This works:

var links = {'one': 1, 'two': 2 };
var setstr = JSON.stringify(links);

localStorage.setItem('strlinks', setstr);
var getstr = localStorage.getItem('strlinks');
console.log(getstr); //Returns what's expected - '{"one":1, "two":2}'

This doesn’t:

var links = $.makeArray($('a'));

alert(links); //Returns list of links
var setstr = JSON.stringify(links);

localStorage.setItem('strlinks', setstr);
var getstr = localStorage.getItem('strlinks');
console.log(getstr); //Returns '[]'

Any ideas about what I’m doing wrong?

Answer 1

links contains circular references, so it can’t be serialized to JSON. Chrome 5.0.375.99 gives the error:

TypeError: Converting circular structure to JSON

You have to somehow remove these circular references. Of course, it depends what info you care about. Here’s a simplified version:

var flatLinks = $.map(links, function(el)
                             {
                              return {href: el.href, text: el.textContent};
                             }); 
var setstr = JSON.stringify(flatLinks);