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Daniel Zotti
Daniel Zotti

Posted on

#LearnedToday: padStart()

The padStart() method is a built-in function in JavaScript that allows you to pad a string with specific characters at the beginning of the string.

I wish it had existed 15 years ago when I was working on a digital clock for a website. I would have written something like this:

const hours = 3;
const minutes = 43;
const seconds = 9;

const time = [hours, minutes, seconds]
                  .map(el => String(el).padStart(2,'0'))
                  .join(":");

// time -> '03:43:09'
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...and of course there is a sister method called padEnd()

🗄 Docs: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/padStart

ℹ Browser support: https://caniuse.com/?search=padStart

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