Javascript Covert object value in array from string to number

Question

I want to convert this

const data = [
 {
   date: "2020-01",
   pageviews: "1548"
 },
 {
   date: "2020-01",
   pageviews: "2000"
 },
]

to

const data = [
 {
   date: "2020-01",
   pageviews: 1548
 },
 {
   date: "2020-01",
   pageviews: 2000
 },
]

but I can't find the a way. I want to use those data to Rechart and the pageviews need to be numbers not strings Can someone help me?

Aalexander · Answer 1 · 2021-01-09T14:17:49.173

3

Solution

You can use forEach to loop over your array.
At each entry parse your pageviews to an int with parseInt()

const data = [
 {
   date: "2020-01",
   pageviews: "1548"
 },
 {
   date: "2020-01",
   pageviews: "2000"
 },
]

console.log(data);

data.forEach((val) => {
  val.pageviews = parseInt(val.pageviews);
});

console.log(data);

edited Jan 09 '21 at 14:17

answered Jan 08 '21 at 21:53

Aalexander

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You're welcome :) if you think this was helpful you can mark this as accepted. – Aalexander Jan 08 '21 at 22:01
1

Using `.map()` instead of `.forEach()` to mutate the elements' properties is pretty weird. – Zsolt Meszaros Jan 08 '21 at 22:11
1

True first I thought I create a new array but I didn't, have updated it. – Aalexander Jan 08 '21 at 22:13

score 0 · Answer 2 · answered Jan 08 '21 at 21:53

<script>
  const data = [
 {
   date: "2020-01",
   pageviews: "1548"
 },
 {
   date: "2020-01",
   pageviews: "2000"
 },
]

 data.forEach(item => {
  item.pageviews = parseInt(item.pageviews)
  return item
 })
 
 console.log(data)
</script>

You can use the parseInt function of JavaScript to convert your String to a Number.

score 0 · Answer 3 · answered Jan 08 '21 at 22:05

If you do not want to alter the original array, you can use Array#map with spread syntax.

const data = [
 {
   date: "2020-01",
   pageviews: "1548"
 },
 {
   date: "2020-01",
   pageviews: "2000"
 },
]
const res = data.map(({pageviews, ...rest})=>({...rest, pageviews: +pageviews}));
console.log(res);

Javascript Covert object value in array from string to number

3 Answers3

Solution