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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.


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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.

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