Assign value to elements in array from Object properties and different Array

Question

Hey I would like to create a new array, from those two elements looking like this:

var a = {szerokosc: 42, wysokosc: 53, dlugosc: null}    // an object
var b = ['dlugosc', '*', 'szerokosc', '+', 'wysokosc']  // an array

The code must work if the correct name is found. At the End I hope to receive an array like this one:

var c = ['0', '*', '42', '+', '53']

If anyone can tell me how to achieve this, I'd appreciate it. Thanks in advance.

Hint: `a[b[2]]` is 42. You should be able to figure it out from there. — , May 04 '22 at 06:27

score 1 · Answer 1 · answered May 04 '22 at 06:32

1

you can do this

var a = {szerokosc: 42, wysokosc: 53, dlugosc: 0}    // an object
var b = ['dlugosc', '*', 'szerokosc', '+', 'wysokosc']  // an array

const transform = (data, dictonary) => data.map(i => dictonary.hasOwnProperty(i)? dictonary[i] : i)

console.log(transform(b, a))

answered May 04 '22 at 06:32

R4ncid

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That's also what I wanted! Thanks! – Szacharz May 06 '22 at 10:38

NightEye · Accepted Answer · 2022-05-04T06:56:43.437

When using a[x] to check the data, simply using b.map(x => a[x] || x) will return [ 'dlugosc', '*', 42, '+', 53 ] due to dlugosc having null value so you need to catch that by checking if the key is present in the object.

Steps:

If the key is present, check if a[x] has a value
If a[x] doesn't have any value, return 0 instead.
If a[x] has a value, return that.
Lastly, if the key isn't present in the object, return the same element

var a = {szerokosc: 42, wysokosc: 53, dlugosc: null}    // an object
var b = ['dlugosc', '*', 'szerokosc', '+', 'wysokosc']  // an array

console.log(b.map(x => Object.keys(a).includes(x) ? !a[x] ? 0 : a[x] : x))

That's what I wanted! Thanks! – Szacharz May 06 '22 at 10:37 — Szacharz, May 06 '22 at 10:37

Assign value to elements in array from Object properties and different Array

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