Issue using JSON.stringify to convert associative array

Question

The issue only happens when the associative array is programmatically apposed to via a literal definition. Using stringify on a literal definition works.

Trying to understand, I used this to test with a literal definition.

var test = {
    voice : { state : 'Ready' }
};
console.log('Stringify test: ' + JSON.stringify(test));

And the output is exactly what I'd expect:

Stringify test: {"voice":{"state":"Ready"}}

This isn't happening when I initialize it programmatically. I should mention that the variable is a private member of an object that I've created, which has accessor/getter methods. Within the constructor, I have:

var states = {};

this.getStates = function()
{
    return states;
}

this.setState = function(newState, mediaType)
{
    states[mediaType] = newState
}

Now I run the same test.

customObj.setState('{ state: 'Ready' }', 'voice');
var test = customObj.getStates();

console.log('Stringify test: ' + JSON.stringify(test));

And the output is not what I expect:

Stringify Test: []

Lastly I double check what the test variable has with:

for(var x in test)
{
    console.log('State in test: ' + x);
    console.log('Value of ' + x + ': ' + JSON.stringify(test[x])); 
}

And with that I get:

State in test: voice
Value of voice: {"state":"Ready"}

OK, so that's telling me that it contains what I'm expecting, but stringify() doesn't format it. Now, I'm left slightly confused what's going on.

Answer 1

I am not sure how you are creating your customObj but the following works:

var CustomObj = function () {
    var states = {};

    this.getStates = function()
    {
        return states;
    }

    this.setState = function(newState, mediaType)
    {
        states[mediaType] = newState
    }
};

var customObj = new CustomObj();
customObj.setState({ state: 'Ready' }, 'voice');

var test = customObj.getStates();
console.log('Stringify test: ' + JSON.stringify(test));

It outputs:

Stringify test: {"voice":{"state":"Ready"}}