Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops `do ... while` Loops

Leandro Severino
Leandro Severino
12,674 Points

Why do I need to use the "do while loop"

let randomNumber = getRandomNumber(10);
let guess;
let guessCount = 0;

function getRandomNumber(upper) {
    let num = Math.floor(Math.random() * 6 ) + 1;
    return num;

while(guess !== randomNumber) {
    guess = prompt('I am thinking of a number between 1 and 10. What is it?');
    guess = parseInt(guess);
    guessCount += 1;

console.log('Number of guesses ' + guessCount);

This works like the do while loop. Why should I use the do while loop?

1 Answer

Steven Parker
Steven Parker
221,291 Points

You'll find that you can generally simulate one type of loop with another, so it's often just "programmer's choice" as to which to use. Often I choose the one that produces the most compact code, when there are several ways to produce the correct result.

Judging by the title, you just happen to be at the point in the course where "do...while" is being introduced.