JavaScript selecting Object Arraylike?

Question

The Problem is the following: I have a JSON file that has objects with the following name: "item0": { ... }, "item1": { ... }, "item2": { ... }. But I can't access them when going through an if method.

What I've done so far:

$.getJSON('/assets/storage/items.json', function(data) {
    jsonStringify = JSON.stringify(data);
    jsonFile = JSON.parse(jsonStringify);

    addItems();
});

var addItems = function() {
    /* var declarations */

    for (var i = 0; i < Object.keys(jsonFile).length; i++) {
        path = 'jsonFile.item' + i;
        name = path.name;
        console.log(path.name);
        console.log(path.type);
    }

}

If I console.log path.name it returns undefined. But if I enter jsonFile.item0.name it returns the value. So how can I use the string path so that it's treated like an object, or is there an other way on how to name the json items.

Possible duplicate of [Access / process (nested) objects, arrays or JSON](https://stackoverflow.com/questions/11922383/access-process-nested-objects-arrays-or-json) — Taplar, Mar 25 '19 at 18:32
var names like `jsonFile` hurt your thinking. JSON is always a string, and can _never_ be anything else. `jsonFile` is an object, so just name it `file`. — Mulan, Mar 25 '19 at 18:34
I would stringify `jsonFile` and then parse it. Just to be sure... (kidding). — trincot, Mar 25 '19 at 18:37

trincot · Answer 1 · 2019-03-25T19:25:01.400

As others stated 'jsonFile.item' + i is not retrieving anything from jsonFile: it is just a string.

Other issues:

It makes no sense to first stringify the data and then parse it again. That is moving back and forth to end up where you already were: data is the object you want to work with
Don't name your data jsonFile. It is an object, not JSON. JSON is text. But because of the above remark, you don't need this variable
Declare your variables with var, let or const, and avoid global variables.
Use the promise-like syntax ($.getJSON( ).then)
Iterate object properties without assuming they are called item0, item1,...

Suggested code:

$.getJSON('/assets/storage/items.json').then(function(data) {
    for (const path in data) {
        console.log(data[path].name, data[path].type);
    }
});

score 0 · Answer 2 · answered Mar 25 '19 at 18:33

What you want is to use object notation using a dynamic string value as a key instead of an object key. So, instead of using something like object.dynamicName you either have use object[dynamicName].

So in your example it would be like this.

path = 'item' + i;
jsonFile[path].name

SerShubham · Answer 3 · 2019-03-25T18:34:43.237

0

I'm afraid you cannot expect a string to behave like an object.

What you can do is this:

path = `item${i}`
name = jsonFile[path].name

edited Mar 25 '19 at 18:34

answered Mar 25 '19 at 18:33

SerShubham

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JavaScript selecting Object Arraylike?

3 Answers3