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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
231,269 Points
Steven Parker
Steven Parker
231,269 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.