CODEWITHSUNDEEP
javascriptarrays
Sparkles the unicorn
Sparkles the unicorn

Reputation: 47

How to add integer to 2-D array items

So lets say I have a log in google's console like this

[[296,279],[304,280],[308,280],[312,280]]

from my script here below

evtSource.onmessage = function(e) {
var obj = JSON.parse(e.data);
var line = JSON.stringify(obj.line)
var size = JSON.stringify(obj.lineWidth)
var color = JSON.stringify(obj.lineColor) // Not needed, but defined anyways.
var chat = JSON.stringify(obj.msg)

if (obj.ident === "") //mee
{
$.post("/draw.php?ing=_index", {
            l: (line),
            w : parseInt(obj.lineWidth) + 2,
            c: ("ffffff"),
            o: ("100"),
            f: ("1"),
            _: ("false")
 })
 console.log(line) //Logs the line. (Example in question.)

How could I add a value of 20 to each item in the array when it logs. So it will log something like this

[[316,299],[324,300],[328,300],[332,300]]

and not like this (The original.)

[[296,279],[304,280],[308,280],[312,280]]

Upvotes: 1

Views: 71

Answers (3)

nick zoum
nick zoum

Reputation: 7325

If you want to print the array with altered data but without altering the original you probably want to use JSON.stringify and JSON.parse to copy the array.

JSON.stringify also accepts a second parameter that allows you to edit the values while the object is being stringified.

var original = [
  [296, 279],
  [304, 280],
  [308, 280],
  [312, 280],
  [[58, 60], [75, 84]],
  4,
  [[5, 9], [[0], [-3]], 8]
];

var json = JSON.stringify(original, function(key, value) {
  return typeof value === "number" ? value + 20 : value;
});
console.log(json);
console.log(JSON.parse(json));

This will work, regardless of how many dimensions the array has (and is ES5 compatible).

Upvotes: 0

Ashish
Ashish

Reputation: 4330

You can use Array.map function. Here we provide a function which will be executed with each element of the array. Which in your case will be another map function.

const line = [[296, 279],[304, 280],[308, 280],[312, 280]]

const out = line.map(arr => arr.map(x => x + 20))
console.log(out)

Upvotes: 0

Jack Bashford
Jack Bashford

Reputation: 44145

Use map:

const arr = [
  [296, 279],
  [304, 280],
  [308, 280],
  [312, 280]
];

const res = arr.map(e => e.map(f => f + 20));

console.log(res);
.as-console-wrapper {
  max-height: 100% !important;
  top: auto;
}

Upvotes: 4

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