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JavaScript JavaScript Loops Working with 'for' Loops The Refactor Challenge – Duplicate Code

Posted by Chun Wang
Chun Wang
1,740 Points

My code printed the numbers but no colors are on them?

let html = '';
let randomNumber = () => {Math.floor(Math.random() * 256)};
let randomRGB;

for(let num = 1; num <= 10; num++) {
randomRGB = `rgb( ${randomNumber()}, ${randomNumber()}, ${randomNumber()} )`;
html += `<div style="background-color: ${randomRGB}">${num}</div>`;
}

My code renders out a white page with white numbers from 1 to 10 without any colors. Could anyone be so nice as to telling me why? Thanks!

1 Answer

Blake Larson
Blake Larson
13,014 Points
Blake Larson
Blake Larson
13,014 Points

Your randomNumber function is returning undefined because you used curly brackets and no return statement. You can just remove the brackets since an arrow function can return the random number implicitly. 

let html = '';
let randomNumber = () => Math.floor(Math.random() * 256); //**No brackets**//
let randomRGB;

for(let num = 1; num <= 10; num++) {
randomRGB = `rgb( ${randomNumber()}, ${randomNumber()}, ${randomNumber()} )`;
html += `<div style="background-color: ${randomRGB}">${num}</div>`;
}