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Get actual date and time with Javascript

I'm developing a website where registrations for a particular event will open on a certain date (say, January 1, 2019) and will close on another date (say, January 10, 2019). I'm using JavaScript to redirect users to the relevant pages if they try to access it on before the 1st or after the 10 of January.
My code so far:
var d = new Date();
var startDate = new Date(2019, 0, 1, 8);
var endDate = new Date(2019, 0, 10, 23, 59);
if(endDate-d<0) // Past expiration date
window.location = "register-closed.html";
else if(startDate-d > 0) // Before starting
window.location = "register-unavailable.html";
The main problem as you might have guessed is that this code takes the local date and time from the user; if I set the date on my device as 2nd January, 2019, I'm able to access the actual register page, even though it's May right now.
I feel this would be a common problem for many, but I've been unable to find any solution to this. How do I get the REAL date and time for my country (India) instead of the device time?
TL;DR
How do I get the actual date and time for a country (in my case, INDIA) using JavaScript? If I can't use vanilla JS, is there some other method to do so?
PS: If you have any solutions that can only be bypassed using methods more complicated than changing your device time, I'll readily accept them. This whole website is just for a high school event, so I don't expect any skilled hackers to spend their time on this :)

This code will get the date (as in the 30th), month, and year. This uses the new Date(); variable type. It has several uses, and you can get the output in whatever order using something like new Date(year, month, day, hours, minutes, seconds, milliseconds). That would output something like Wed May 22 2019 10:46:32 GMT-0400 (Eastern Daylight Time).
var todaysDate = new Date();
var date = todaysDate.getDate();
var month = todaysDate.getMonth();
var year = todaysDate.getFullYear();
if(date === 10 || month === 0 || year === 2019){
//January is 0 because counting starts at 0
...
}
https://www.w3schools.com/jsref/jsref_obj_date.asp

you should take a look to this topic as it seems to answer to your problem using only vanilla JS. Hope it helps :)

Set date() to midnight in users timezone with moment.js

I use moment.js to display a UTC date in the users local timezone:
var date = new Date(Date.UTC(2016,03,30,0,0,0));
var now = new Date();
var diff = (date.getTime()/1000) - (now.getTime()/1000);
var textnode = document.createTextNode(moment(date).format('dddd, DD.MM.YYYY') + ' a las ' + moment(date).format('HH:mm A'));
document.getElementsByClassName("date")[0].appendChild(textnode.cloneNode(true));
I later use the diff variable to show a countdown timer.
I would like to show a different countdown timer to everyone in their local time zone. (Using the difference till its midnight in their time zone, not in UTC)
But I am struggeling to get it work. Instead of using var date = new Date(Date.UTC(2016,03,30,0,0,0)); I probably need to use some function of moment.js that gives me till midnight in the users time zone.
The best example would be new years eve. If I use UTC everyone would have the same counter (9 hours left) but in different parts of the world this wouldn't make sense. For someone in australia it should be 2 hours left, and for someone in the US 14 hours.

I'm not sure that I fully understand your question, but I'll give you some general advice and tips.
When using moment.js, there is very little need to ever use the Date object. Only use it for interacting with other APIs that expect a Date object.
To get a moment in UTC, just use moment.utc(...), passing the appropriate arguments, such as moment.utc([2016,3,30]) or moment.utc('2016-04-30') for midnight April 30th UTC.
If you want to convert that back to the user's local time, use the .local() function. For example, moment.utc('2016-04-30').local() will create a moment with the equivalent local time to the UTC time provided.
If you want a moment in the user's local time, then that would be moment(...), such as moment([2016,3,30]) or moment('2016-04-30') for midnight April 30th local time.
You can difference two moments using the diff function, which can give the answer in specific units, such as m1.diff(m2, 'seconds') where m1 and m2 are moment objects.
You don't need to call format twice. Just encapsulate any text you want outputed with square brackets. .format('dddd, DD.MM.YYYY [a las] HH:mm A')
You might look into moment's locale support. If I'm not mistaken, "a las" indicates Spanish, however it's not always "a las", but sometimes "a la", if the hour is 1. Also, moment only uses those words in its .calendar() function, such as when producing a phrase like "mañana a las 13:17". A regular date formatted with .format('LLLL') in the Spanish locale would be something like: "sábado, 19 de marzo de 2016 13:17". So, you might want to verify that "a las" is exactly what you want in every case.
The title to this question was how to set a date to midnight. For that, I recommend using moment's startOf function. m.startOf('day') will give set the moment m to the start of the day, which is usually midnight. Keep in mind that not every local day actually starts at midnight in every time zone. Due to anomalies like daylight saving time, some days might start at 1:00. For example, this occurs in Brazil on October 16th this year.
Also, if you created the moment in UTC mode, you may wish to convert it back to local mode first before setting it to the start of the day. If you don't want to change the original moment object, be sure to clone it first.
Putting this all together:
var m1 = moment.utc([2016,3,30]);
var m2 = m1.clone().local().startOf('day');
var now = moment();
var diff = m1.diff(now, 'seconds');

javascript dates converted to bst time on android devices when using Firefox

I have a web application that runs on Chrome without any problems on a Android Device but when running it on Firefox it converts the "newvalue" to BST time zone instead of GMT Standard Time.
var now = new Date();
var start = new Date();
var newvalue = new Date(now - start);
The newvalue timezone output is GMT+0100(BST) but should actually be GMT+0000(GMT Standard Time)
Firefox is adding an an extra hour.
I have tried to convert to UTC and GMT but doesn't seem to work.
Any ideas?

OK so ... Ermmm ... I'm not clear on what you're doing with the line:
var newvalue = new Date(now - start);
Are you trying to time something?
Regardless, the first thing this line does is to subtract start from now, and give the difference between the 2 dates in milliseconds. Assuming this happens basically instantly, the result will be approximately (if not precisely) 0 milliseconds.
When you create a date and pass in a single parameter like this, you are asking for the date as it was, X milliseconds after epoch. Epoch is defined as Thursday Jan 1st 1970 (for reasons I won't go into). So by creating a new Date with a parameter of 0, you're just asking the browser to give you epoch.
Why Firefox decides to give you epoch in BST instead of GMT, I'll grant is actually pretty odd (since Jan 1st is clearly not in British Summer Time). But this fact is probably irrelevant, given that this is almost certainly NOT what you are trying to achieve here. If you're trying to time something, I'd suggest you probably just want to do:
var newvalue = start - now;
Where newvalue is now the difference in time. Note: I have swapped now and start around, since in your example start is defined after now, and hence this will give you the positive time difference.
EDIT IN RESPONSE TO COMMENT
To be clear, I'm suggesting that you DON'T create a new Date object with the result of the subtraction.
If you want to get the number of milliseconds between the two times using dates, just subtract them:
var start = new Date();
// do time consuming stuff
var end = new Date();
var difference = end - start; // NOT: var difference = new Date(end - start)

Resolved the issue by turning the two dates in to a UTC date and then finding the difference between the two dates using milliseconds.
This then works on Android.
Thanks for your assistance

javascript date object changes

I have been reading up on dates for days, seemingly going in circles here. I have a string in a DB that looks like this
2012,03,13,01,31,38
I want to create a js date object from it so...
new Date(2012,03,13,01,31,38);
Easy enough, right? But it comes back as
2012-04-13 05:31:38 +0000
So the month is off by 1 and the time is off by 4 hours (maybe DST or Timezone related???). I simply want a date that matches the one I provided. Its driving me nuts, dealing with these JS date objects.
How can I be sure the date object is the exact same date and time as the string suggests, I have no need for Timezone or DST changes, simply a date that matches a string.
More specifics regarding application:
My application for this need is for an iphone app I am developing in Titanium (which builds using JS). Basically, part of my app involves logging data and with that log I collect the device's current date and time. I save all of this information to a mySQL database. The field in the database looks like this format: "2012-02-16 00:12:32"
Here is where I start to run into problems. I am now offering the ability to edit the log, including the date and time it was logged. In order to use an iPhone "picker", I must convert the string above into a JS date object again. This usually screws things up for me. I essentially need to create a new date object with the date above, with timezone and dst being completely irrelevant, so that when I save back to the DB, its just the string above, modified as per the users request. It needs to not matter whether they are editing in pennsylvania or china, they are editing the same log date.
Sorry if this has been confusing. I am having a hard time figuring out this whole date stuff.

This depends on what your string is. If that string is UTC time, you need to parse it as that. If it's local time, you need to parse it as local time. You can make a helper method like this for that part:
function getDate(utc, year, month, day, hour, minute, second) {
if(utc) {
var utc = Date.UTC(year, month - 1, day, hour, minute, second);
return new Date(utc);
} else {
return new Date(year, month - 1, day, hour, minute, second);
}
}
Now, to parse your string, you can use this:
function fromString(utc, str) {
var parts = str.split(',');
var year = parts[0];
var month = parts[1];
var day = parts[2];
var hour = parts[3];
var minute = parts[4];
var second = parts[5];
return getDate(utc, year, month, day, hour, minute, second);
}
which you can use like this for your example:
var d = fromString(true, '2012,02,13,00,31,38'); // If UTC
var d = fromString(false, '2012,02,13,00,31,38'); // If local time
Here's a working jsFiddle that you can play with:
http://jsfiddle.net/rNqXW/
which also shows two ways to print the date (UTC or local). Hope this helps.

I had the same problem. There are two reasons for the weird time change:
Use new Date(Date.UTC(2012,03,13,01,31,38)) to avoid the time change.
Note that the month is zero based! Months go from 0 to 11 for this function.

JavaScript Addition Date Functions

I don't really know too much about core JavaScript, just a dot of jQuery. But I know jQuery is not necessary for what I need here:
I want to use the getdate function to find out the server's day of the week. Then add a bunch of clauses like:
if its Monday add 6 to the date and return the date in MM/DD/YYYY form.
if its Tuesday add 5 to the date and return the date in MM/DD/YYYY form.
if its Wednesday add 4 to the date and return the date in MM/DD/YYYY form.
and so on until Sunday when it will add 0.
So lets say todays Monday, it will return 1/8/2012
And in real dates today's Sunday so it will really return 1/1/2012
Then I just want to call a document.write function to write the MM/DD/YYYY it returns into my HTML document.
Can anybody help me? I can clarify if you need me to...

getDay() returns the day of the week, Sunday = 0, Monday = 1, etc, etc.
So say today was Monday getDay() would return 1, which means daysToAdd would be 5.
Once we know how many days we want to add we can create a new date and add those days. We do this by getting today in milliseconds and then adding the number of days (daysToAdd) in milliseconds.
We convert days to milliseconds by multiplying by 24*60*60*1000 which is the number of milliseconds in a day.
I add 1 to the month because JavaScript returns 0 based month, but for display purposes we want to format it so that January for example is 1 not zero.
function getEndOfWeek() {
var today = new Date();
var weekDay = today.getDay();
// if you want the week to start on Monday instead of Sunday uncomment the code below
//weekDay -= 1;
//if(weekDay < 0) {
// weekDay += 7;
//}
var daysToAdd = 6 - weekDay;
var newDate = new Date(today.getTime() + daysToAdd *24*60*60*1000);
var month = newDate.getMonth() + 1;
var day = newDate.getDate();
var year = newDate.getFullYear();
var formatedDate = month + "/" + day + "/" + year;
return formatedDate;
}
You could implement in your code like so, JavaScript:
$(function() {
$("#TheDate").html(getEndOfWeek());
});
Your HTML would be something like this:
The week ends on <span id="TheDate"></span>.
You can find the jsFiddle here: jsFiddle
If you want to adjust the weekday so that you consider Monday the start of the week instead of Sunday you can do the following after you get the weekDay:
weekDay -= 1;
if(weekDay < 0) {
weekDay += 7;
}

var day = 1000*60*60*24
, nextSunday = new Date(+new Date() + day*(7-((0|(+new Date()/day)%7-3)||7)));
alert(
(101+nextSunday.getMonth()).toString().substr(1) + '/' +
(100+nextSunday.getDate()).toString().substr(1) + '/' +
nextSunday.getFullYear()
)

As fas as adding dates in JavaScipt my "DateExtensions" library does this well enough, I think. You can get it here:
http://depressedpress.com/javascript-extensions/dp_dateextensions/
Once refenced you can call "add()" as a method for any valid date and pass it any of many date parts (second, minutes, days, hours, etc). So assuming "curDate" is a valid JavaScript date object you can add 5 days like this:
newDate = curDate.add(5, "days");
Using a negative value will subtract:
newDate = curDate.add(-5, "days");
Once you get the date you want you can the use the library's dateFormat() method to display it like so:
curDate.dateFormat("MM/DD/YYYY");
There's full documentation at the link.
Integer Values for Day of Week
As for getting the integer value you want, it's actually easier that it looks (and you don't need an "if" just some math). The getDay() method of date returns the day of week with Sunday as "0" and Saturday as "6". So the week, from Sunday, would normally be:
0,1,2,3,4,5,6
First, you want to reverse that scale. That's easily done via subtraction by taking 7 (to total number of members of the set) from the value. This gives you this scale:
-7,-6,-5,-4,-3,-2,-1
We're getting closer. You want the first value to be zero as well. The simplest way (I think) to do this is to get the modulus (remainder) of the value by the total number of members. All this basically does is make "-7" a zero and leave the rest alone giving us this:
0,-6,-5,-4,-3,-2,-1
Almost done. Finally you don't want negative numbers so you need to use the Math.abs() method to eliminate the sign (get the absolute value) leaving us with our desired result:
0,6,5,4,3,2,1
For all the talk the acutual code is pretty compact:
Math.abs((cnt-7)%7)
Wrapping this into the original example gives us:
newDate = curDate.add(Math.abs((curDate.getDay()-7)%7), "days");
Server Vs Client
However take nnnnnn's comment to heart: in JavaScript the getDate() function gets the current date/time of the machine that it's running on - in the case of a web page that's the client, not the server.
If you actually meant the client time them you're set and done. If you really need the server time however that's annoying-to-impossible. If you own the server then it's actually not to hard to set up a rule that includes the current server in a cookie withing each fufilled request (you could then use my cookie library, also at the site above, to access the information!)
It's messier but depending on the server you might also be able to create an old-school server-side include that adds a bit of JavaScript to each page (preferably as a marked replace in the header) that hard-codes the date as a global variable.
You might also create a web service that returns the current server time but the client-overhead for that is insane compared to the data being delivered.
If the server's NOT yours (and you can't get the owner to provide the above) then the only real potential option is to do a straight http call and examine the HTTP "Date" header. Again however the overhead on this is immense compared to the return but it's really the only way. Any system like this would have to be very flexible however as any particular server might not return the date header or might not return it correctly.
Even if it does work understand that you might still not be getting the "server" time - or at least not the server you want. In a tiered architecture, for example an application server might render then page and hand it to a web server to return - you'd be getting the web server time, not the app server. Any number of appliances might also rewrite the headers (for example it's common to use dedicated SSL appliances to offload all the encryption work - these often re-write the headers themselves).
Sorry to get overly technical - JavaScript is definately one area where there's unfortunately rarely a "simple question". ;^)
Good Luck!