How to Convert All Elements in an Array to Integer in JavaScript

How to convert all elements in an array to integer in JavaScript?

You need to loop through and parse/convert the elements in your array, like this:

var result_string = 'a,b,c,d|1,2,3,4',
    result = result_string.split("|"),
    alpha = result[0],
    count = result[1],
    count_array = count.split(",");
for(var i=0; i<count_array.length;i++) count_array[i] = +count_array[i];
//now count_array contains numbers

You can test it out here. If the +, is throwing, think of it as:

for(var i=0; i<count_array.length;i++) count_array[i] = parseInt(count_array[i], 10);

Convert string array to integer array

Use map() and parseInt()

var res = ['2', '10', '11'].map(function(v) {  return parseInt(v, 10);});
document.write('<pre>' + JSON.stringify(res, null, 3) + '<pre>')

convert string arrays to integer then get the sum

You can easily achieve this result first parsing

"[3, 43, 3, 3, 5]"

[3, 43, 3, 3, 5]

using JSON.parse and then use reduce to add the array elements

const array = [
  "[3, 43, 3, 3, 5]",
  "[3, 43, 3, 3, 5]",
  "[3, 43, 3, 3, 5]",
  "[3, 43, 3, 3, 5]",
  "[3, 43, 3, 3, 5]",
  "[3, 43, 3, 3, 5]",
];

const result = array.map((a) => JSON.parse(a).reduce((acc, curr) => acc + curr));

console.log(result);

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Convert integer array to string array in JavaScript

You can use map and pass the String constructor as a function, which will turn each number into a string:

sphValues.map(String) //=> ['1','2','3','4','5']

This will not mutate sphValues. It will return a new array.

How to convert nested arrays with strings to numbers in JavaScript?

Use Array#map method with a recursive approach for the nested array.

function conv(arr) {
  // iterate over the array
  return arr.map(function(v) {
    // if the element is an array call the function recursively
    // or parse the number and treat NaN as 0
    return Array.isArray(v) ? conv(v) : Number(v) || 0;
  })
}

const array = [  ["4000", "2000", "1000", ""],  ["6000", "7000", "3000"]];const array1 = ["1000", "5000", "3000"];
function conv(arr) {  return arr.map(function(v) {    return Array.isArray(v) ? conv(v) : Number(v) || 0;  })}
console.log(conv(array));console.log(conv(array1));

How to convert a string of numbers to an array of numbers?

My 2 cents for golfers:

b="1,2,3,4".split`,`.map(x=>+x)

backquote is string litteral so we can omit the parenthesis (because of the nature of split function) but it is equivalent to split(','). The string is now an array, we just have to map each value with a function returning the integer of the string so x=>+x (which is even shorter than the Number function (5 chars instead of 6)) is equivalent to :

function(x){return parseInt(x,10)}// version from techfoobar
(x)=>{return parseInt(x)}         // lambda are shorter and parseInt default is 10
(x)=>{return +x}                  // diff. with parseInt in SO but + is better in this case
x=>+x                             // no multiple args, just 1 function call

I hope it is a bit more clear.

convert array of numbers that are strings into array of numbers

You can do

var arrayOfNumbers = arrayOfStrings.map(Number);

MDN Array.prototype.map

For older browsers which do not support Array.map, you can use Underscore

var arrayOfNumbers = _.map(arrayOfStrings, Number);

converting array to different types (lodash/js)

Use Array#map with the index of the loop.

var a = ["2013", "72", "68", "76", "75", "76", "73"];  a = a.map(function (b, i) {    return i ? Number(b) : b;});
console.log(a);

How to Convert All Elements in an Array to Integer in JavaScript