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

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

Cast Value to Array

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:

Flowchart:

Live Demo:

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

For more Practice: Solve these Related Problems:

• Write a JavaScript program that converts a non-array value into an array, wrapping it if necessary.
• Write a JavaScript function that checks if the input is already an array and returns it; otherwise, it creates a new array containing the input.
• Write a JavaScript program that handles various data types and always returns an array version of the input.

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