Javascript Array isArray()

let numbers = [1, 2, 3, 4];

// checking whether numbers is an array or not
console.log(Array.isArray(numbers));

let text = "JavaScript";

// checking whether text is an array or not
console.log(Array.isArray(text));

// Output:
// true
// false

isArray() Syntax

The syntax of the isArray() method is:

Array.isArray(value)

The isArray() method, being a static method, is called using the Array class name.

isArray() Parameters

The isArray() method takes a single parameter:

• value - The value to be checked.

isArray() Return Value

The isArray() method returns:

• true if the passed value is Array
• false if the passed value is not Array

Note: This method always returns false for TypedArray instances.

Example 1: Using isArray() Method

let fruits = ["Apple", "Grapes", "Banana"];

// checking whether fruits is an array or not
console.log(Array.isArray(fruits));

let text = "Apple";

// checking whether text is an array or not
console.log(Array.isArray(text));

Output

true
false

In the above example, we have used the isArray() method to find out whether fruits and text are arrays or not.

(Array.isArray(fruits)) returns true since fruits is an array object and (Array.isArray(text)) returns false since text is not an array (it's a string).

Example 2: isArray() to Check Other Data Types

// passing an empty array []
console.log(Array.isArray([])); // true 

// we have created an array with element 7 and
// passed that value to isArray()
console.log(Array.isArray(new Array(7))); // true

// passing a boolean value
console.log(Array.isArray(true)); // false

// passing undefined
console.log(Array.isArray(undefined)); // false

// not passing any argument in isArray()
console.log(Array.isArray()); // false 

Output

true
true
false
false
false

Also Read:

• JavaScript Program to Check if An Object is An Array