w3resource

JavaScript: Cast the provided value as an array if it's not one

JavaScript fundamental (ES6 Syntax): Exercise-61 with Solution

Write a JavaScript program to cast the provided value as an array if it's not one.

  • Use Array.prototype.isArray() to determine if val is an array and return it as-is or encapsulated in an array accordingly.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2
// Define a function 'castArray' to ensure that the input value is wrapped in an array.
const castArray = val => (Array.isArray(val) ? val : [val]);

// Test the function with different types of input values.
console.log(castArray('w3r'));    // Output: ['w3r']
console.log(castArray([100]));    // Output: [100]

Output:

["w3r"]
[100]

Visual Presentation:

JavaScript Fundamental: Cast the provided value as an array if it's not one

Flowchart:

flowchart: Cast the provided value as an array if it's not one

Live Demo:

See the Pen javascript-basic-exercise-61-1 by w3resource (@w3resource) on CodePen.


Improve this sample solution and post your code through Disqus

Previous: Write a JavaScript program to create a function that invokes the method at a given key of an object, optionally adding any additional supplied parameters to the beginning of the arguments.
Next: Write a JavaScript program to chain asynchronous functions.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.



Become a Patron!

Follow us on Facebook and Twitter for latest update.

It will be nice if you may share this link in any developer community or anywhere else, from where other developers may find this content. Thanks.

https://w3resource.com/javascript-exercises/fundamental/javascript-fundamental-exercise-61.php