I'm trying to get the difference between 2 timestamps.

I have a array with saved timestamps and when i loop over them i'm trying to get the difference between then and now but it logs as "sent:", "Hours - 0 - Minutes 0 - Seconds - 0" and i was wondering if anyone knew why?

let messages = [{
  username: "test one",
  message: "testing one",
  time: new Date()
}, {
  username: "test two",
  message: "testing two",
  time: new Date()
}];

const duration = (difference) => {
  let secondsInMiliseconds = 1000,
    minutesInMiliseconds = 60 * secondsInMiliseconds,
    hoursInMiliseconds = 60 * minutesInMiliseconds;

  let differenceInHours = difference / hoursInMiliseconds,
    differenceInMinutes = differenceInHours % 1 * 60,
    differenceInSeconds = differenceInMinutes % 1 * 60;

  return {
    "hours": Math.floor(differenceInHours),
    "minutes": Math.floor(differenceInMinutes),
    "seconds": Math.floor(differenceInSeconds)
  }
};

console.log("Wait One minute befor logging / loop");

setTimeout(() => {
  for (let i = 0; i < messages.length; i  ) {
    let now = new Date();

    let time = duration(now - messages[i].time);
    let sent = `Hours - ${time.hours} - Minutes ${time.hours} - Seconds - ${time.hours}`;
    console.log("sent:", sent);
  }
}, 30000);

<iframe name="sif1" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

Sorry if my english is not good.

CodePudding user response：

As the comments mentioned, there seems to be some confusion about the modulo operator priority and then there is the bug about time.hour being used three times. Here's a fixed, simplified and shortened version. Since the variables declared in duration are only used once, and since it's a simple function, I took the liberty to inline the calculation.

let messages = [{
  username: "test one",
  message: "testing one",
  time: new Date()
}, {
  username: "test two",
  message: "testing two",
  time: new Date()
}];

const duration = (difference) => {
  return {
    hours: Math.floor(difference / (1000 * 60 * 60)),
    minutes: Math.floor((difference / (1000 * 60)) % 60),
    seconds: Math.floor((difference / 1000) % 60)
  }
};

console.log("Wait One minute befor logging / loop");

setTimeout(() => {
  for (let i = 0; i < messages.length; i  ) {
    let now = new Date();
    let time = duration(now - messages[i].time);
    let sent = `Hours - ${time.hours} - Minutes ${time.minutes} - Seconds - ${time.seconds}`;
    console.log("sent:", sent);
  }
}, 30000);