Array Operations and Methods

Adding an Element to an Array

There are 2 ways to add a new element to an array.

Let's say we have this array: var students = ["John", "Ann", "Kevin"];

The index of “John”, “Ann” and “Kevin” is 0, 1 and 2 respectively. If you want to add more elements to the students array, you can do it like this:

1. Option 1:

2. Option 2:

You can use the built-in push() method to add an element at the end of the array.
For example:
students.push("Emma")
students.push("Rose")

Now the array elements are: ["John", "Ann", "Kevin", "Emma", "Rose"]

Changing the Elements of an Array

Let's say we have this array: var students = ["John", "Ann", "Kevin"];

This statement changes or replaces the value of the first element in the students array:

Now the array elements are: ["Ray", "Ann", "Kevin"]

Removing an Element from an Array

You can use the pop() method to remove the last element from an array.

Let's say we have this array: var students = ["John", "Ann", "Kevin"];

This statement changes the value of the first element in the students array:

Now the array elements are: ["John", "Ann"]

Other Important Array Methods

sort( ) - Sorts the elements of an array
reverse( ) - Reverses the order of the elements of an array -- the first becomes the last, and the last becomes the first.

Arrays in JS - Manipulating Arrays