push element in array javascript at index code example

Example 1: insert into array js

// for me lol... pls don't delete!
// use splice to insert element
// arr.splice(index, numItemsToDelete, item); 
var list = ["hello", "world"]; 
list.splice( 1, 0, "bye"); 
//result
["hello", "bye", "world"]

Example 2: insert item into array specific index javascript

myArray.splice(index, 0, item);

Example 3: javascript add array to array at index

a1.splice(2, 0, ...a2);

Example 4: add new element by index js

const arr = [ 1, 2, 3, 4 ];
arr[5] = 'Hello, world!';

console.log(arr); // [ 1, 2, 3, 4, <1 empty item>, 'Hello, world!' ]
console.log(arr.length); // 6