Member Avatar for smoothe19

How do I push new values to the following javascript array?

json = {"cool":"34.33","alsocool":"45454"}

I tried

json.push("coolness":"34.33");

but it didnt work

Edited by smoothe19
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Dani AI

Generated

accidentally tried to use an array method on a plain object. As already notes, your value is an object, not an array; ’s suggestions are on the right track. Push only works on arrays — to add a property to an object set a key, or merge objects with native helpers.

Simple options (native):

let data = {a: "34.33", b: "45454"};

// add or overwrite one property
data["coolness"] = "34.33";
let merged = Object.assign({}, data, {coolness: "34.33"});
// or with modern syntax
let copy = {...data, coolness: "34.33"};

If your starting value is a JSON string, parse it first, adjust the object, then stringify if you need a string.

Troubleshooting and tips

  • Check type before using push: use Array.isArray(x) (because typeof returns "object" for arrays).
  • Use bracket notation when the key is dynamic or contains characters that aren’t valid identifier names.
  • Prefer const/let over var, and avoid naming variables json (it’s confusing — JSON is the format).
  • If you want immutability, create a new object (spread or Object.assign) instead of mutating the original.
  • If values should be numbers, convert them (Number()/parseFloat()) instead of leaving them as strings.

If you intended an array of items, convert or create an array and then use push to append elements (e.g., arr.push({coolness: 34.33})). Otherwise, add properties to the object as shown above.

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Member Avatar for lambing

you could jQuery's extend method.

var obj1 = {"cool":"34.33","alsocool":"45454"};
var obj2 = {"coolness":"34.33"};
$.extend(obj1, obj2);

The value of the first object will contain obj2.

console.log(obj1);

The above statement will log something like this:

{"cool":"34.33","alsocool":"45454", "coolness":"34.33"}

If you don't want to use jQuery, you can try the native and easy way by doing this:

json.coolness = "34.33";

Everything in JavaScript is an object, you can assign properties to objects easily and set it's value

Edited by lambing because: More explanation
Member Avatar for Airshow

Sir Saula,

{"cool":"34.33","alsocool":"45454"} is a plain javascript object not an array.

Add extra properties as per Lambing's suggestions.

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