concat two arrays in react code example

Example 1: combine two arrays javascript

let arr1 = [0, 1, 2];
let arr2 = [3, 5, 7];
let primes = arr1.concat(arr2);

// > [0, 1, 2, 3, 5, 7]

Example 2: concatenate multiple arrays javascript

const array1 = ['a', 'b', 'c'];
const array2 = ['d', 'e', 'f'];
const array3 = [...array1, ...array2];

console.log(array3);
// expected output: Array ["a", "b", "c", "d", "e", "f"]

Example 3: concat two arrays in react

var array1 = [1,2,3,4];
var array2 = [5,-6,7,8.5];

const concatArr = (arr1, arr2, sep) => arr1.map(function (num, idx) {
  return num.toString().concat(sep,(arr2[idx]).toString())
});

console.log(concatArr(array1,array2,"#"))// ["1#5", "2#-6", "3#7", "4#8.5"]