add an array to another array on an index typescript code example

Example: push elements of array to another array typescript

// Same array push
let arr1 = [0, 1, 2];
let arr2 = [3, 4, 5];
arr1.push(...arr2);

// New array push
let arr1 = [1, 2];
let arr2 = [3, 4];
let newArr = arr1.concat(arr2);