JS | Asynchronous JS and callbacks

README.md

JS | Asynchronous JS and callbacks

Console Clock - example

clock.js

const second = 1000;
let counter = 0;

function concatZero(num) {      // when num = 22
  return ('0' + num).slice(-2); // "022"  --> "22"
}

function updateClock() {
  let dateObj = new Date();
  const seconds = dateObj.getSeconds();
  const minutes = dateObj.getMinutes();
  const hours = dateObj.getHours();
  // const miliseconds = dateObj.getMilliseconds();
  
  const timeNow = concatZero(hours) + ':' + concatZero(minutes) + ':' + concatZero(seconds);

	console.log(timeNow);
  counter++;
  if ( counter > 10 ) {
    clearInterval(clockInterval)
  }
}

const clockInterval = setInterval(updateClock, second);