Objects are not valid as a React child when I mapping an object

Question

I'm starting react and can't solve my problem. I have an object

   modes= {
        "easyMode": {
        "field": 5
        },
        "normalMode": {
        "field": 10
        },
        "hardMode": {
        "field": 15
        }
        }

And I need to map this modes(easyMode, normalMode and hardMode), but I know that I can't map an object, only arrays. Right, but this also doesn't work

const arrayOfObjects = [{ modes }];

return (
    <ul> {arrayOfObjects.map(mode=> <li key={mode}>{mode} </li>)}</ul>)

How I need to do this right?

If you want to get the keys into an array you can use `Object.keys(modes)` and then map that — Nick Parsons, Dec 04 '21 at 11:30
@NickParsons, ok, but in that way I have an error 'arrayOfObjects.keys(modes).map is not a function' — Vlada Novaturova, Dec 04 '21 at 11:41
That is different code to what I suggested above? `Object.keys(modes).map()` is what I meant — Nick Parsons, Dec 04 '21 at 11:43

score 0 · Answer 1 · answered Dec 04 '21 at 11:40

I think it's a duplicate question and you can find a complete answer in this question here

but as a fast answer, for the objects, you have to iterate like this:

Object.keys(modes).map ( mode => {
   console.log(mode,modes[mode]) // you can access the values like this
})

Nat · Accepted Answer · 2021-12-04T11:54:22.157

0

You can use Object.keys() to get an array with modes keys

const modes = {
  easyMode: {
    field: 5,
  },
  normalMode: {
    field: 10,
  },
  hardMode: {
    field: 15,
  },
};

const modesKeys = Object.keys(modes); // ['easyMode','normalMode','hardMode' ]

return (
  <ul> {modesKeys.map(mode => <li key={mode}>{mode}</li>)}</ul>
)

edited Dec 04 '21 at 11:54

answered Dec 04 '21 at 11:46

Nat

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Thank you so much! I really like this variant! – Vlada Novaturova Dec 04 '21 at 11:52

Objects are not valid as a React child when I mapping an object

2 Answers2