Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

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

Leandro Severino
Leandro Severino
12,674 Points
Posted by 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
231,275 Points
Steven Parker
Steven Parker
231,275 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.