Develop Reference

Getting same unix time stamp for two different times in javascript

I had two ical format timestamps and I want to convert them to normal time first and then to unix time.
Here this is the function I've been using to convert normal time to unix timestamp:
var normal_to_unix = function (date_string) {
var date = new Date(date_string);
return date.getTime() / 1000;
}
This function is fine since date is already in UTC and I need not do any conversions.
Now this is the function I've been using to convert ical time to unix time. The ical time in my case is like "20180603T150000Z".
var ics_to_unix = function (ics_string) {
var year = ics_string.slice(0, 4);
var month = ics_string.slice(4, 6);
var date = ics_string.slice(6, 8);
var hours = ics_string.slice(9, 11);
var minutes = ics_string.slice(11, 13);
var seconds = ics_string.slice(13, 15);
var milliseconds = 0;
console.log(year, month, date, hours, minutes, seconds, milliseconds); // This is example output 2018 06 03 15 00 00 0
return normal_to_unix((new Date(year, month, date, hours, minutes, seconds, milliseconds)).toDateString())
}
Now the problem is I'm getting the same unix time for "20180603T150000Z" and "20180603T160000Z" which are supposed to give different timestamps and it is 1530576000 for both of them.
Is there anything that I'm missing ? Thanks in advance.
Please have a look at this for live example

Several points here:
The toDateString() method returns the date portion of a Date object in human readable form in American English. For your example it is `Tue Jul 03 2018', perhaps that is not what you want.
new Date creates date in your local timezone, which could play well if you use it together with toString(), which will also return the string for date in your local timezone. But it will be subject to daylight saving changes, so I'd avoid using that method.
Another thing I'd like to avoid converting back and forth between strings and dates, since it does a lot of unnecessary computations.
I'd suggest to use the following:
var ics_to_unix = function (ics_string) {
var year = parseInt(ics_string.slice(0, 4));
var month = parseInt(ics_string.slice(4, 6)) - 1; // Jan is 0
var date = parseInt(ics_string.slice(6, 8));
var hours = parseInt(ics_string.slice(9, 11));
var minutes = parseInt(ics_string.slice(11, 13));
var seconds = parseInt(ics_string.slice(13, 15));
return Date.UTC(year, month, date, hours, minutes, seconds) / 1000;
}
I have added explicit conversion of strings to numbers, adjusted the month to match what is used in javascript and also removed the extra call.

Remove Seconds/ Milliseconds from Date convert to ISO String

I have a date object that I want to
remove the miliseconds/or set to 0
remove the seconds/or set to 0
Convert to ISO string
For example:
var date = new Date();
//Wed Mar 02 2016 16:54:13 GMT-0500 (EST)
var stringDate = moment(date).toISOString();
//2016-03-02T21:54:13.537Z
But what I really want in the end is
stringDate = '2016-03-02T21:54:00.000Z'

There is no need for a library, simply set the seconds and milliseconds to zero and use the built–in toISOString method:
var d = new Date();
d.setSeconds(0,0);
document.write(d.toISOString());
Note: toISOString is not supported by IE 8 and lower, there is a pollyfil on MDN.

While this is easily solvable with plain JavaScript (see RobG's answer), I wanted to show you the Moment.js solution since you tagged your questions as "momentjs":
moment().seconds(0).milliseconds(0).toISOString();
This gives you the current datetime, without seconds or milliseconds.
Working example: http://jsbin.com/bemalapuyi/edit?html,js,output
From the docs: http://momentjs.com/docs/#/get-set/

A non-library regex to do this:
new Date().toISOString().replace(/.\d+Z$/g, "Z");
This would simply trim down the unnecessary part. Rounding isn't expected with this.

A bit late here but now you can:
var date = new Date();
this obj has:
date.setMilliseconds(0);
and
date.setSeconds(0);
then call toISOString() as you do and you will be fine.
No moment or others deps.

Pure javascript solutions to trim off seconds and milliseconds (that is remove, not just set to 0). JSPerf says the second funcion is faster.
function getISOStringWithoutSecsAndMillisecs1(date) {
const dateAndTime = date.toISOString().split('T')
const time = dateAndTime[1].split(':')
return dateAndTime[0]+'T'+time[0]+':'+time[1]
}
console.log(getISOStringWithoutSecsAndMillisecs1(new Date()))
function getISOStringWithoutSecsAndMillisecs2(date) {
const dStr = date.toISOString()
return dStr.substring(0, dStr.indexOf(':', dStr.indexOf(':')+1))
}
console.log(getISOStringWithoutSecsAndMillisecs2(new Date()))

This version works for me (without using an external library):
var now = new Date();
now.setSeconds(0, 0);
var stamp = now.toISOString().replace(/T/, " ").replace(/:00.000Z/, "");
produces strings like
2020-07-25 17:45
If you want local time instead, use this variant:
var now = new Date();
now.setSeconds(0, 0);
var isoNow = new Date(now.getTime() - now.getTimezoneOffset() * 60000).toISOString();
var stamp = isoNow.replace(/T/, " ").replace(/:00.000Z/, "");

Luxon could be your friend
You could set the milliseconds to 0 and then suppress the milliseconds using suppressMilliseconds with Luxon.
DateTime.now().toUTC().set({ millisecond: 0 }).toISO({
suppressMilliseconds: true,
includeOffset: true,
format: 'extended',
}),
leads to e.g.
2022-05-06T14:17:26Z

You can use the startOf() method within moment.js to achieve what you want.
Here's an example:
var date = new Date();
var stringDateFull = moment(date).toISOString();
var stringDateMinuteStart = moment(date).startOf("minute").toISOString();
$("#fullDate").text(stringDateFull);
$("#startOfMinute").text(stringDateMinuteStart);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.11.2/moment.js"></script>
<p>Full date: <span id="fullDate"></span></p>
<p>Date with cleared out seconds: <span id="startOfMinute"></span></p>

let date = new Date();
date = new Date(date.getFullYear(), date.getMonth(), date.getDate());
I hope this works!!

To remove the seconds and milliseconds values this works for me:
const date = moment()
// Remove milliseconds
console.log(moment.utc(date).format('YYYY-MM-DDTHH:mm:ss[Z]'))
// Remove seconds and milliseconds
console.log(moment.utc(date).format('YYYY-MM-DDTHH:mm[Z]'))

We can do it using plain JS aswell but working with libraries will help you if you are working with more functionalities/checks.
You can use the moment npm module and remove the milliseconds using the split Fn.
const moment = require('moment')
const currentDate = `${moment().toISOString().split('.')[0]}Z`;
console.log(currentDate)
Refer working example here:
https://repl.it/repls/UnfinishedNormalBlock

In case for no luck just try this code
It is commonly used format in datetime in the SQL and PHP
e.g.
2022-12-25 19:13:55
console.log(new Date().toISOString().replace(/^([^T]+)T([^\.]+)(.+)/, "$1 $2") )

Date and time based json element using javascript

I have a json response like this :
{
"NO_INSPECTION": "55",
"NO_SURAT": "00055",
"DATE_OF_DESCRIPTION": "2015-12-21 03:08:24"
}
How can I convert the data in "DATE_OF_DESCRIPTION" Into date and time. Date should be dd-mm-yyy format and time should be in HH:mm format. (A sample value of DATE_OF_DESCRIPTION is 2015-12-21 03:08:24)
I have tried new Date(response.DATE_OF_DESCRIPTION); but no success. How can I achieve this?

Without the use of other libraries and assuming the output will always be zero-padded and the same length, I would do this:
var response = {
DATE_OF_DESCRIPTION: "2015-12-21 03:08:24"
}
var raw = response.DATE_OF_DESCRIPTION;
var datePart = raw.split(' ')[0];
var timePart = raw.split(' ')[1];
var year = datePart.substring(0, 4);
var month = datePart.substring(5, 7);
var day = datePart.substring(8, 10);
var hours = timePart.substring(0, 2);
var minutes = timePart.substring(3, 5);
// NOTE: Month is 0 indexed
var date = new Date(year, month - 1, day);
var dateTime = new Date(year, month - 1, day, hours, minutes);
console.log(date);
console.log(dateTime);
This gives the output
Mon Dec 21 2015 00:00:00 GMT+1000 (E. Australia Standard Time)
Mon Dec 21 2015 03:08:00 GMT+1000 (E. Australia Standard Time)
(I'm from Australia, so your timezone will vary)

JavaScript has a fixed date format and you can change it, thus the Date object won't help you this time. As I see it, you want to split that date, so it's pretty easy if you provide it in this format "dd-mm-yyy HH:mm":
response.DATE_OF_DESCRIPTION = response.DATE_OF_DESCRIPTION.split(" "); // date and time are separated by an space
var date = response.DATE_OF_DESCRIPTION[0];
var time = response.DATE_OF_DESCRIPTION[1];
BTW, if you want to parse a date in a specified format, why don't you use any library for that? Many of them are almost as reliable and fast as native methods. Give them a try ;)
You could also format the date, so it fits the JS specs but, why reinvent the wheel? Libraries will do this for you and you'll get optimal cross-browser results!
I've googled "javascript date parsing library" and this is what I've found:
http://momentjs.com/ <--- I think that's what you're looking for!

JavaScript New Date()

I have the following JavaScript code but for some reason time is not including minutes:
var austDay = $("#<%= hiddenFieldTime.ClientID %>").val().split(" ");
var year = austDay[0];
var months = austDay[1];
var days = austDay[2];
var time = austDay[3];
var timeUntil = new Date(parseInt(year), parseInt(months),
parseInt(days), parseInt(time));
When I debug using firebug these are my value:
$("#ctl00_hiddenFieldTime").val() = "2011, 5, 6, 14:20:00"
year = "2011,"
months = "5,"
days = "6,"
time = "14:20:00"
timeUntil = Date {Mon Jun 06 2011 14:00:00 GMT-0400 (Eastern Daylight Time)}
As you can see, timeUntil is set to 14:00:00 instead of 14:20:00

parseInt(time) is the problem
Here are the few dates initialization format
var d = new Date();
var d = new Date(milliseconds);
var d = new Date(dateString);
var d = new Date(year, month, day, hours, minutes, seconds, milliseconds);

According to the Mozilla documentation for Date, the following constructors are supported:
new Date()
new Date(milliseconds)
new Date(dateString)
new Date(year, month, day [, hour, minute, second, millisecond ])
This means that in your constructor, when you pass parseInt(time), that parameter is only used for the hour parameter. You need to pass a separate parameter for minutes, and yet another one if you happen to want seconds.
Also, you should always pass a base parameter to parseInt, like so:
parseInt(hours, 10)
Otherwise when you go to parse a value with a leading 0 such as parseInt('08'), the value will be interpreted as an octal number.

Your last conversion is going to drop everything after the colon:
parseInt("14:20:00"); // 14
The whole conversion is rather bloated, I suggest trying to format the string initially in a format you can pass as is to JS's Date constructor, which will make life easier.

parseInt ("14:20:00") returns 14

Javascript convert seconds to a date object

How can I convert seconds into a datetime object in javascript.
Examples:
1.3308313703571
1.6324722385401
This is from a series of points and when they occurred. I understand 1.23323 more then seconds, but I can not change the value, being pulled from an api.

You can try like this:
function toDateTime(secs) {
var t = new Date(1970, 0, 1); // Epoch
t.setSeconds(secs);
return t;
}
Info on epoch date.

You can pass unix timestamp milliseconds as an argument to the Date constructor:
const secs = 30;
const output = new Date(secs * 1000);
console.log(output);

#UVM's answer is helpful, but slightly incomplete if you're dealing with timezones (i.e. UTC vs local time). With timezones, start with UTC using Date.UTC and Date.setUTCSeconds to get a true UTC date and time.
function toDateTime(secs) {
var t = new Date(Date.UTC(1970, 0, 1)); // Epoch
t.setUTCSeconds(secs);
return t;
}
You can then use a library like Moment to convert/format it to a local timezone.

your example values have a decimal.. looking like you are trying to convert 1.something seconds into a date..
Meanwhile check this example here on the correct seconds to date conversion.. you could view their js sources.

The question seems to have already been answered but this may be helpful for those attempting to do something similar to ruby's Time.at() method.
function formatDateTime(input){
var epoch = new Date(0);
epoch.setSeconds(parseInt(input));
var date = epoch.toISOString();
date = date.replace('T', ' ');
return date.split('.')[0].split(' ')[0] + ' ' + epoch.toLocaleTimeString().split(' ')[0];
};

I dunno how it be 10 years ago, but now it can solve just doing next:
let sec = 1628618888939
let time = new Date(sec)
let normalDate = new Date(sec).toLocaleString('en-GB',{timeZone:'UTC'})
time: "Tue Aug 10 2021 21:08:08 GMT+0300 (Eastern European Summer Time)"
normalDate: "10/08/2021, 18:08:08"
If in the future u will have problems like this, I can advise read about functions that relate to your question, and solution will come.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleString