JavaScript Arrays - Day 20

Arrays are one of the Type of Object. Its used to store many variable in a single variable using Index values. In objects we use name:value property to store and when call the object the same procedure.

But Array is little different..

We call Arrays using Index. The first index is 0 (Zero-based Index).

To Create an Array :---

var array_name = [item1, item2, ...];

<p id="demo"></p>
<script>

var cars = ["Saab", "Volvo", "BMW"];

document.getElementById("demo").innerHTML = cars;

</script>
Output: Saab,Volvo,BMW


Another way of creating Array is
var Array_name = new Array( );

E.g: 

<p id="demo"></p>

<script>

var cars = new Array("Maruthi", "Fiat", "Nissan");

document.getElementById("demo").innerHTML = cars;

</script>

Output: Maruthi, Fiat, Nissan

Accessing Array
1. Using indexing Method

<p id="car_info"></p>

<script>

var cars = ["Maruthi", "Fiat", "Lamborgini"];

document.getElementById("car_info").innerHTML = cars[0];

</script>

Output: Maruthi

2.  Calling the Name inside curly braces

<p id="first"></p>

<script>

var person = {firstName:"Parathan", lastName:"Thiyaa", age:19};

document.getElementById("first").innerHTML = person["firstName"];

</script>

Output:  Parathan

Length of Array : This will return the number of values in the Array.
<p id="demo"></p>

<script>

var fruits = ["Banana", "Orange", "Apple", "Mango"];

document.getElementById("demo").innerHTML = fruits.length;

</script>


Output:4

typeof

This will return the Data Type of the variable..

E:g-

<p id="type"></p>

<script>

var person = ["Parathan", "Saravanan", "Varshanan"];

document.getElementById("type").innerHTML = typeof person;

</script>

Output: object

Array.isArray() : This method will check if that variable is an array or not.

<p id="test"></p>

<script>

var fruits = ["Banana", "Orange", "Apple", "Mango"];

document.getElementById("test").innerHTML = Array.isArray(fruits);

</script>

Output: true

Another way of instanceof array is used to test the array

<p id="demo"></p>

<script>

var fruits = ["Banana", "Orange", "Apple", "Mango"];

document.getElementById("demo").innerHTML = fruits instanceof Array;

</script>

Output: true