how to add function to an array code example

Example 1: js add function to array

//create an new function that can be used by any array
Array.prototype.second = function() {
  return this[1];
};

var myArray = ["item1","item2","item3"];
console.log(myArray.second());//returns 'item2'

Example 2: how to add to an array

var ar = ['one', 'two', 'three'];
ar[3] = 'four'; // add new element to ar