Trying to return fetch's response array ends up with undefined

Question

There's my code:

   fetch(data)
    .then(blob => blob.json())
    .then(newData => array.push(newData))
let be = array[0].id;

I'd like to access my array data, but I end up with undefined and I don't know why.
After reloading page

However it works just fine in console.
Working good with console.log

I've been reading all over the internet for hours, but I can't seem to understand why does it work like that.

score 1 · Accepted Answer · answered Feb 11 '18 at 19:05

1

fetch run asynchronously so, you can do something like this.

let array = [];
let be = '';

fetch(data)
 .then(blob => blob.json())
 .then(newData => {
    array.push(newData);
    be = array[0].id;
 });

As soon as you call your fetch method, while it wait's response from the server or from wherever you are trying to get the information, the i/o doesn't stop and starts executing the rest of the code while waiting the response from server.

answered Feb 11 '18 at 19:05

Adeel Imran

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It does work indeed, thank you. (I'd upvote but i'm noob in terms of overstack and don't know how to do it ) – Lovs Feb 11 '18 at 19:18

Trying to return fetch's response array ends up with undefined

1 Answers1