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Javascript: Get epoch date as from predefined date is using todays date instead [duplicate]

This question already has answers here:
Convert UNIX to readable date in javascript
(3 answers)
Closed 4 years ago.
JSFiddle: https://jsfiddle.net/u8w3v9fd/1/
I am trying to get the day, month and year from a date that is passed form the database in the format: DD/MM/YYYY. However I can't even seem to get the correct date to show.
Here is my code:
var time = "1522843537";
var regDateOriginal = new Date(time);
var regDate = new Date();
regDate.getMonth(regDateOriginal);
regDate.getHours(regDateOriginal);
regDate.getDate(regDateOriginal);
document.write("<p style='color: #fff'>" + regDate.getDate(regDateOriginal) + "</p>");
As you can see, this is returning:
21
Which is todays date. It should be 4
I have googled it and hacked around with various versions for the past 45 mins. I am a junior and would really appreciated a nicely commented piece of code so I can learn instead of just copying and pasting.
Thank you for your help.

From here
var time = 1522843537;
var d = new Date(0); // The 0 there is the key, which sets the date to the epoch
d.setUTCSeconds(time);
console.log(d.getDate());
Of course, you can still do all the other Date functions as needed.

How can I convert this string "07/10/2017 18:30 PM" to JavaScript Date type

I am trying to read all dates in a table and see if those dates are old dates than current date time and if those are old dates then highlight those dates with some color.
Here is my Javascript code
$(".ticket-gird-td-duedate").each(function(i, e) {
debugger;
var dueDateAsString = $(e).text();
console.log(dueDateAsString);
var dueDate = new Date(dueDateAsString);
var currentdate = new Date();
if (dueDate < currentdate) {
//mark date in red color
console.log("I need to change color for this date as this is past date" + dueDate);
}
});
Problem here is dueDateAsString comes as "07/10/2017 18:30 PM"
And when I am doing
new Date("07/10/2017 18:30 PM")
it fails with invalid date error
Invalid Date
How can I convert my string date to Javascript date and proceed to compare it with current date?

That isn't a valid date, as you either have 24hr format or AM|PM 12hr format.
This works:
new Date('07/10/2017 18:30'); // No 'PM' after the 24hr time
Also note that JS dates are mutable, so todayDate and check will hold the same date value, but check will be a number.

You call this one first
todayDate.setDate(todayDate.getDate() - 5);
It will update todayDate to 5 days ago. Then you just assign it to check or you todayDate further.
var check = todayDate;
Hope this helps.

You can do this by using moment.js library (yet another terrific way to achieve date parsing).
Moment.Js library is freely available. You can use either a minified or full version of this library as you require. In this
library all the operations are performed on a moment object so the
date or time is stored in this library as a moment object only. So
this moment object is the core of this entire library. You can find
this library at Moment.js site's home page.
Add momentjs library reference into your project - https://momentjs.com/downloads/moment.js
updated code with moment.js would be:
var todayDate = new moment().format("MM/DD/YYYY h:mm:ss a");
var yesterday = todayDate.toLocaleString();
var check = moment(todayDate, "MM/DD/YYYY h:mm:ss a").add('days', -5);
alert("Your Old Date is- " + todayDate);
alert(check);
alert("Your Old Date is- " + yesterday);
JavaScript fiddle

Date restrictions on user input in JavaScript

I am trying to have a date entry box which has the following restrictions. Date must be today's date or earlier, but not more than 1 year previous. I have the following line:
if (myFDGDT - todayDate > 0 || (myFDGDT - todayDate)/86400000 < -365)
The first portion of that creates the appropriate alert when some enters a date after today's date. Not sure about the best way to cap the entry to a year previous. Attempted a few items, but the above was just an example of my last attempt. This is also written in a dependency and not in the Global JavaScript of our entry client.

Here is a snippet that will generate a Date object that is one year ago. You can compare against it as needed using greater than/less than operators.
var oneyear = new Date('01/01/1971'); // from unix epoch
var now = new Date();
var oneyearago = new Date(now - oneyear);
alert(oneyearago);

If you are manipulating dates a lot in your app you should consider using the momentjs library. For your problem the solution would be something like:
var momentdate = moment(date);
if (momentdate.isAfter(momentdate.add(1, 'year') ||
momentdate.isBefore(momentdate.startOf('day')) {
// Invalid date?
}
Hope this helps.

How to subtract date/time in JavaScript? [duplicate]

This question already has answers here:
How do I get the difference between two Dates in JavaScript?
(18 answers)
Closed 8 years ago.
I have a field at a grid containing date/time and I need to know the difference between that and the current date/time. What could be the best way of doing so?
The dates are stored like "2011-02-07 15:13:06".

This will give you the difference between two dates, in milliseconds
var diff = Math.abs(date1 - date2);
In your example, it'd be
var diff = Math.abs(new Date() - compareDate);
You need to make sure that compareDate is a valid Date object.
Something like this will probably work for you
var diff = Math.abs(new Date() - new Date(dateStr.replace(/-/g,'/')));
i.e. turning "2011-02-07 15:13:06" into new Date('2011/02/07 15:13:06'), which is a format the Date constructor can comprehend.

You can just substract two date objects.
var d1 = new Date(); //"now"
var d2 = new Date("2011/02/01"); // some date
var diff = Math.abs(d1-d2); // difference in milliseconds

If you wish to get difference in wall clock time, for local timezone and with day-light saving awareness.
Date.prototype.diffDays = function (date: Date): number {
var utcThis = Date.UTC(this.getFullYear(), this.getMonth(), this.getDate(), this.getHours(), this.getMinutes(), this.getSeconds(), this.getMilliseconds());
var utcOther = Date.UTC(date.getFullYear(), date.getMonth(), date.getDate(), date.getHours(), date.getMinutes(), date.getSeconds(), date.getMilliseconds());
return (utcThis - utcOther) / 86400000;
};
Test
it('diffDays - Czech DST', function () {
// expect this to parse as local time
// with Czech calendar DST change happened 2012-03-25 02:00
var pre = new Date('2012/03/24 03:04:05');
var post = new Date('2012/03/27 03:04:05');
// regardless DST, you still wish to see 3 days
expect(pre.diffDays(post)).toEqual(-3);
});
Diff minutes or seconds is in same fashion.

Unless you are subtracting dates on same browser client and don't care about edge cases like day light saving time changes, you are probably better off using moment.js which offers powerful localized APIs. For example, this is what I have in my utils.js:
subtractDates: function(date1, date2) {
return moment.subtract(date1, date2).milliseconds();
},
millisecondsSince: function(dateSince) {
return moment().subtract(dateSince).milliseconds();
},

You can use getTime() method to convert the Date to the number of milliseconds since January 1, 1970. Then you can easy do any arithmetic operations with the dates. Of course you can convert the number back to the Date with setTime(). See here an example.

Compare to dates Javascript? [duplicate]

This question already has answers here:
Closed 12 years ago.
Possible Duplicate:
Compare 2 dates with JavaScript
Hi,
I'm working on form validation for my application and i want to know where i would be to start looking at to find date comparison eg a start date and an end date. The dates inputted in to my application are in the form: DD/MM/YYYY.
Thanks in Advance,
Dean

If you are using the Javascript Date object, you can simply do:
var startDate = new Date();
var endDate = getEndDate();
if (endDate < startDate)
alert("Houston, we've got a problem!");
EDIT: Changed naming a bit just to stick to camelCase convention, even though I despise it.

this function lets you convert dates to timestamps with wich you could work:
http://caioariede.com/arquivos/strtotime.js

First, you'll want to parse the text into Date objects, then use the language's built-in date comparison. For example:
var dateStr = document.getElementById('foo').value;
var date = Date.parse(dateStr);
var dateStr2 = document.getElementById('foo2').value;
var date2 = Date.parse(dateStr2);
if (date < date2) {
// ...
}