Sum of to times using javascript

Question

can anyone tell me how to do sum of two time using javascript (momentjs) for exemple the sum of:

2:44:56 and 2:50:56

i tried that but doesnt work:

2:44:56 + 2:50:56

any suggestions please??

Answer 1

Momentjs has a duration object that can be used to add or subtract two or more timespans.

const a = moment.duration('02:44:56');
const b = moment.duration('02:50:56');

const c = a.add(b);

console.log(c.hours() );
console.log(c.minutes() );
console.log(c.seconds() );

Answer 2

You can do it like this. Use add method on moment object and pass your data.

let x = moment({  
         hours:'2', 
         minutes:'44',
         seconds:'56'})
       .add({ 
         hours:'2',
         minutes:'50', 
         seconds:'56' })
 console.log(x)

or dynamically pass data

let time = {
   hours: 2,
   minutes:44, 
   seconds: 56
}
let time2 = {
   hours: 2,
   minutes:50, 
   seconds: 56
}
let y = moment(time)
         .add(time2)
console.log(y)

Answer 3

One could add the seconds, then calculate the carry value and add that to the sum of minutes and so on. That can be easily done with reduce:

function sum(date1, date2){
  date1 = date1.split(":");
  date2 = date2.split(":");
  const result = [];

  date1.reduceRight((carry,num, index) => {
    const max = [24,60,60][index];
    const add =  +date2[index];
    result.unshift( (+num+add+carry) % max );
    return Math.floor( (+num + add + carry) / max );
  },0);

 return result.join(":");
}

console.log(
  sum("2:44:56" , "2:50:56" )
);

Try it

Answer 4

The code:

var t1 = moment('2:44:56', 'HH:mm:ss');
var t2 = '2:50:56';
var parsed_t2 = t2.split(':') // [2, 50, 56]

var r = t1.add({
  hours: parsed_t2[0], // 2
  minutes: parsed_t2[1], // 50
  seconds: parsed_t2[2], // 56
});

The process:

1. Parse the string as a moment object (helping it with defining the format we're using;
2. Split the time we want to add to the t1 by using the split() function effectively splitting our t2 into an array where we have [hours, minutes, seconds]
3. Add the the times together using the moments add() method.

---

Working example

Answer 5

moment() function takes hours, minutes, seconds as arguments and return a moment object which has a add() method that also can take hours, minutes, seconds as arguments and return total times.

Try addTimes(time1, time2)

function addTimes(time1, time2) {
   let [hours1, minutes1, seconds1] = time1.split(':');
   let [hours2, minutes2, seconds2] = time2.split(':');
   return moment({ hours: hours1, minutes: minutes1, seconds: seconds1 })
       .add({ hours: hours2, minutes: minutes2, seconds: seconds2 })
       .format('h:mm:ss');
}

console.log(addTimes('2:44:56', '2:50:56'));

Answer 6

Good old JS solution:

var base = new Date(0);
var t1 = new Date(base);
var t2 = new Date(base);
t1.setUTCHours(2,45,50);
t2.setUTCHours(2,50,50);
var t = new Date(t1.getTime() + t2.getTime() - base.getTime());

result = t.getUTCHours() + ":" + t.getUTCMinutes() +":" + t.getUTCSeconds();
console.log(result);

Note that JS automatically converts time of the day to GMT timezone hence we need to use UTC version of time functions.