push array index javascript code example

Example 1: javascript push in specific index

arr.splice(index, 0, item);
//explanation:
inserts "item" at the specified "index",
deleting 0 other items before it

Example 2: how to push items in array in javascript

let items = [1, 2, 3]
items.push(4); // items = [1, 2, 3, 4]