JavaScript: Get a random element from an array

JavaScript fundamental (ES6 Syntax): Exercise-149 with Solution

Random Element from Array

Write a JavaScript program to get a random element from an array.

• Use Math.random() to generate a random number.
• Multiply it by Array.prototype.length and round it off to the nearest whole number using Math.floor().
• This method also works with strings.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2

// Define the sample function
const sample = arr => arr[Math.floor(Math.random() * arr.length)];

// Select a random element from the array [3, 7, 9, 11]
console.log(sample([3, 7, 9, 11])); // Output: (random number from the array)

Output:

11

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-149-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that returns a random element from an array using Math.random.
• Write a JavaScript function that selects an element at a random index from a given array.
• Write a JavaScript program that handles empty arrays gracefully when retrieving a random element.

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