timer callback in object javascript code example

Example 1: javascipt delay

function sleep(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));
}

console.log("Hello");
sleep(2000).then(() => { console.log("World!"); });

Example 2: javascript settimeout

var timeoutID;

function delayedAlert() {
  timeoutID = window.setTimeout(window.alert, 2*1000, 'That was really slow!');
}

function clearAlert() {
  window.clearTimeout(timeoutID);
}