How to convert hours:minutes using javascript

Question

I am currently working on Jvascript datetime part in that getting NaN error while converting hours and minutes to seconds like strtotime in PHP so I want to know how to convert minutes and seconds like the way we do in strtotime in PHP.

var d = new Date();
var total = d.getHours() + ":" + d.getMinutes();
var ts = Date.parse(total);
document.write(ts);

In output getting error NaN

just use `total`, why are you trying to reconvert to a timestamp with `Date.parse()`? — Federico klez Culloca, Jul 18 '18 at 12:22
@FedericoklezCulloca i have requirement of convert hours:minutes to seconds that's why i am using this. — Anonymous, Jul 18 '18 at 12:23
https://stackoverflow.com/questions/4048204/javascript-equivalent-of-phps-strtotime — Jax Teller, Jul 18 '18 at 12:23
Then you don't need to convert to hours:minutes, why are you doing it? — Federico klez Culloca, Jul 18 '18 at 12:24

mikeb · Answer 1 · 2018-07-18T13:19:21.200

3

This is a sort of inane question, but here's the number of seconds in the hours and minutes of that number:

var d = new Date();
var total = (d.getHours() * 60 * 60) + (d.getMinutes() * 60);
document.write(total);

edited Jul 18 '18 at 13:19

answered Jul 18 '18 at 12:23

mikeb

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This line with `Date.parse` is unnecesary as it parses real result in some insane way and hence this displays really big number instead of correct `total` – barbsan Jul 18 '18 at 12:45

Wais Kamal · Answer 2 · 2018-07-18T12:51:23.390

1

First of all, Date.parse() takes a string of a specific format (such as Jul 18, 2018). Second, it will not convert the date to seconds, but will return the number of milliseconds since January 1, 1970 00:00:00 GMT.

If you need to convert hh:mm to seconds, the correct approach is to multiply the value of getHours() by 3600 and multiply the value of getMinutes() by 60, then sum up the two values.

var d = new Date();
var timeinsecs = d.getHours() * 3600 + d.getMinutes() * 60;
document.write(timeinsecs);

While if you need to get the time in seconds from January 1, 1970 00:00:00 GMT till the current time, you will need to parse the current date then divide by 1000:

var d = new Date();
document.write(Date.parse(d) / 1000);

edited Jul 18 '18 at 12:51

answered Jul 18 '18 at 12:32

Wais Kamal

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thanks actually i was not aware of this Date.parse will calculate in milliseconds . – Anonymous Jul 18 '18 at 12:36
Glad to help :) – Wais Kamal Jul 18 '18 at 12:37

score 0 · Accepted Answer · answered Jul 18 '18 at 12:25

0

Just get hours and minutes, then sum them multiplying hours * 3600 and minutes * 60, like this

var d = new Date();
var total = d.getHours() * 3600 + d.getMinutes() * 60;
document.write(total)

answered Jul 18 '18 at 12:25

Federico klez Culloca

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thanks for your answer ,I was doing in wrong way this is what i needed. – Anonymous Jul 18 '18 at 12:32

Jeremy Kahan · Answer 4 · 2018-07-18T13:00:29.473

If you want to follow your original approach of not doing the math by hand, you need to include a date before the time (any date should do, could be today if you wish) and convert ms to seconds (both of these for the reasons Wais Kamal pointed out) as follows.

var d = new Date();
var total = d.getHours() + ":" + d.getMinutes();
var someDate ='July 4, 1776';//works, but maybe safer to choose since 1990
total=someDate+', '+total;
var ts = Date.parse(total);
document.write((ts- Date.parse(someDate))/1000);

How to convert hours:minutes using javascript

4 Answers4