How to add leading zero to a number in JavaScript
I had the need to add a leading zero when the number I had was less than 10, so instead of printing “9” on the screen, I had “09”.
The use case being I wanted to display the length of a video, and 5:04
is more logical than 5:4
to say a video is 5 minutes and 4 seconds.
Here’s how I did it:
Math.floor(mynumber)
.toString()
.padStart(2, '0')
All of this is native to JavaScript, using the Math built-in library
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