JSON stringify displays null while object is not null

Question

This is probably a very basic problem, as I'm a javascript beginner.

I've got an object which console.log describes as the following :

As you can see, it holds a certain amount of data.

But when I try to display it as JSON on an HTML page using JSON.stringify, the only thing that displays is this :

[[],[],[],[],[],[],[],[],[]]

Which is very weird, because if instead of JSON.stringify, I do for example this :

div.innerHTML = myObject[0].ArmyName;

....well I get "ARMY_1" to display. So the object is correctly populated. But if I do

div.innerHTML = JSON.stringify(myObject)

or

div.innerHTML = JSON.stringify(myObject[0])

then I only get null / empty data to display.

Am I doing something wrong ?

Those are all empty arrays with some custom properties. Arrays in JavaScript always have numerical indexes. Use objects instead. — JJJ
– JJJ, Commented Apr 2, 2018 at 9:47
I get this data from another program and I can't really change the way it is made. But can you tell me if I could convert this "custom array" to object ? — Rackover
– Rackover, Commented Apr 2, 2018 at 9:49
It's very likely that you're making a mistake when you retrieve the data. That's where it should be fixed. — JJJ
– JJJ, Commented Apr 2, 2018 at 9:52
I guess you are resetting the data of the object/array after you are assigning it to innerHTML. Because objects when assigned are only going to copy the references. Put your code in codepen and see whats happening. — Mani
– Mani, Commented Apr 2, 2018 at 9:58

Jonas Wilms · Accepted Answer · 2018-04-02 09:52:35Z

2

Just convert your pseudo 2d array into an array of objects:

 array = array.map(el => Object.assign({}, el))

And you should tell the one who created that API that this is not the way to go.

answered Apr 2, 2018 at 9:52

Jonas Wilms

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