Convert Object to Array returns Undefined

Question

Here is the object I'm trying to convert into array:

{ 1: {..}, 2: {..}, 3: {..}, 4: {..}, 5: {..}}

This is the function I'm using to convert the Object into array:

const convertObjectToArray = (object) => {
  const array = [];

  if (object) {
    Object.keys(object).forEach((key) => {
      array.push({[key]: object[key]});
    })
    console.log('object inside function', object);
    console.log('array inside function', array);
    return array;
  } else {
    return [];
  }
}

And here the render method:

class PostList extends React.Component {
  render() {
    const { postList } = this.props;

    const array = convertObjectToArray(postList);

    console.log('postList', postList);
    console.log('array', array);

    return (
      <div>
        {array.map(({ id, ...otherCollectionProps }) => {
          return (
            <Post key={id} {...otherCollectionProps} />
          );
        })}
      </div>
    );
  }
};

The problem here is that I get the error of "Cannot read property 'map' of undefined", when inside the console I get logged the array with values - and so I don't understand how I get the undefined value

These are the objects/arrays I get logged into console I have tried following these other issues: 1. Object to Array returns undefined 2. Mapping Object to convert object to array

But they were not useful enough to get this issue fixed

Thanks in advance for your suggestions!

Is this your entire code? I see no reason why array would be undefined. — Adam Jeliński
– Adam Jeliński, Commented Apr 8, 2020 at 9:39
Try use method Array.from() to covert object to array. Here is the documentation: developer.mozilla.org/pl/docs/Web/JavaScript/Referencje/Obiekty/… — Krzysztof Antosik
– Krzysztof Antosik, Commented Apr 8, 2020 at 9:39
No that's not my entire code; I fixed anyway the issue following Dennis Vash's answer. Thanks everyone for trying help though! — ale917k
– ale917k, Commented Apr 8, 2020 at 9:49

Dennis Vash · Accepted Answer · 2020-04-08 09:35:18Z

1

Try using Object.values which returns an array of object's values.

const object = { 1: { a: 'a'}, 2: { b: 'b'}, 3: { c: 'c'} }
const convertObjectToArray = Object.values;

console.log(convertObjectToArray(object));

answered Apr 8, 2020 at 9:35

Dennis Vash

54.2k12 gold badges120 silver badges133 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

ale917k Over a year ago

Tried it and it actually works, thanks a lot!! For avoiding future issues like this one, do you know why I was getting an undefined value with the previous code?

Dennis Vash Over a year ago

Can't find a mistake on those snippets, it should come from some other place

Collectives™ on Stack Overflow

Convert Object to Array returns Undefined

1 Answer 1

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related