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Format JSON DateTime

I currently have all my dates being returned with the letter T in my JSON Strings. EX: 2019-02-03T06:48:07. Is there a way to change the JSON String to return as 02-03-2019 06:48:07?
I am also using javascript to load the dates currently into a data table.

You can convert your string into a Date object and then format it like this:
let jsonString = "2019-02-03T06:48:07";
// You should set your own timezone and options.
console.log(new Date(jsonString).toLocaleString('en-US', {hour12: false}))
For more information, visit: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleString

The T is there because this is a standard ISO 8601 format. It makes it very easy to parse on the client side:
var myDate = new Date('2019-02-03T06:48:07')
With myDate you can then do whatever formatting you wish. Assuming you have another function to handle leading zeros, that could be something like:
var myFormattedDate = padLeft(myDate.getMonth() + 1, '0') + '-' +
padLeft(myDate.getDay(), '0') + '-'
myDate.getFullYear() + ' ' +
// etc
Note that your timestamp lacks any timezone information. With this code it will be interpreted on the client side in whatever the local timezone of the user is. If it is UTC time, then you can correct for this by adding either 'Z' or '+00:00' onto the timestamp before parsing in the Date constructor.
If you are able to add a library to assist, this all becomes much easier with moment.js:
myFormattedDate = moment('2019-02-03T06:48:07').format('MM/DD/YYYY HH:mm:ss');

Convert time format string with moment.js

I am getting a date string in format '2020-01-22T19:52:13.180Z' from an API. I am using momentjs library for datetime manipulation. But I am not able to find a format in momentjs to convert the above string into valid javascript date or moment object. [I have no control over the response returned from the API].

You can get javascript date object by using the Date constructor itself.
new Date("2020-01-22T19:52:13.180Z").

You can format Date manually as you want. Refer to the following code.
let current_datetime = new Date("2020-01-22T19:52:13.180Z")
let formatted_date = current_datetime.getDate() + "-" + (current_datetime.getMonth() + 1) + "-" + current_datetime.getFullYear()
console.log(formatted_date)

No format support in Date object [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Extending JavaScript's Date.parse to allow for DD/MM/YYYY (non-US formatted dates)?
Convert dd-mm-yyyy string to date
Entered a date in textbox, for example: 05/09/1985, and I wanted to convert it to 05-Sep-1985 (dd-MMM-yyyy) format. How would I achieve this? Note that the source format may be dd-mm-yyyy or dd/mm/yyyy or dd-mmm-yyyy format.
Code Snippet:
function GetDateFormat(controlName) {
if ($('#' + controlName).val() != "") {
var d1 = Date.parse($('#' + controlName).val());
if (d1 == null) {
alert('Date Invalid.');
$('#' + controlName).val("");
}
var array = d1.toString('dd-MMM-yyyy');
$('#' + controlName).val(array);
}
}
This code returns 09-May-1985 but I want 05-Sep-1985. Thanks.

You might want to use helper library like http://momentjs.com/ which wraps the native javascript date object for easier manipulations
Then you can do things like:
var day = moment("12-25-1995", "MM-DD-YYYY");
or
var day = moment("25/12/1995", "DD/MM/YYYY");
then operate on the date
day.add('days', 7)
and to get the native javascript date
day.toDate();

Update
Below you've said:
Sorry, i can't predict date format before, it should be like dd-mm-yyyy or dd/mm/yyyy or dd-mmm-yyyy format finally i wanted to convert all this format to dd-MMM-yyyy format.
That completely changes the question. It'll be much more complex if you can't control the format. There is nothing built into JavaScript that will let you specify a date format. Officially, the only date format supported by JavaScript is a simplified version of ISO-8601: yyyy-mm-dd, although in practice almost all browsers also support yyyy/mm/dd as well. But other than that, you have to write the code yourself or (and this makes much more sense) use a good library. I'd probably use a library like moment.js or DateJS (although DateJS hasn't been maintained in years).
Original answer:
If the format is always dd/mm/yyyy, then this is trivial:
var parts = str.split("/");
var dt = new Date(parseInt(parts[2], 10),
parseInt(parts[1], 10) - 1,
parseInt(parts[0], 10));
split splits a string on the given delimiter. Then we use parseInt to convert the strings into numbers, and we use the new Date constructor to build a Date from those parts: The third part will be the year, the second part the month, and the first part the day. Date uses zero-based month numbers, and so we have to subtract one from the month number.

Date.parse recognizes only specific formats, and you don't have the option of telling it what your input format is. In this case it thinks that the input is in the format mm/dd/yyyy, so the result is wrong.
To fix this, you need either to parse the input yourself (e.g. with String.split) and then manually construct a Date object, or use a more full-featured library such as datejs.
Example for manual parsing:
var input = $('#' + controlName).val();
var parts = str.split("/");
var d1 = new Date(Number(parts[2]), Number(parts[1]) - 1, Number(parts[0]));
Example using date.js:
var input = $('#' + controlName).val();
var d1 = Date.parseExact(input, "d/M/yyyy");

Try this:
function GetDateFormat(controlName) {
if ($('#' + controlName).val() != "") {
var d1 = Date.parse($('#' + controlName).val().toString().replace(/([0-9]+)\/([0-9]+)/,'$2/$1'));
if (d1 == null) {
alert('Date Invalid.');
$('#' + controlName).val("");
}
var array = d1.toString('dd-MMM-yyyy');
$('#' + controlName).val(array);
}
}
The RegExp replace .replace(/([0-9]+)\/([0-9]+)/,'$2/$1') change day/month position.

See this http://blog.stevenlevithan.com/archives/date-time-format
you can do anything with date.
file : http://stevenlevithan.com/assets/misc/date.format.js
add this to your html code using script tag and to use you can use it as :
var now = new Date();
now.format("m/dd/yy");
// Returns, e.g., 6/09/07

date string formatting

The best way to take a string that is formated like...
YYYY-MM-DD
and make it appear like...
MM/DD/YYYY
The reason it is not a javascript date object is because I am working with massive amounts of data and these dates are being pulled from a database.
I see no need to convert it to a date object.

How about:
s.substr(5,2) + '/' + s.substr(8) + '/' + s.substr(0,4)

You can use a regular expression in JavaScript (assuming JS because your question is tagged as such):
var date = "2010-05-09";
var formatted = date.replace(/([0-9]{4})-([0-9]{2})-([0-9]{2})/, "$2/$3/$1")
What I like about this more than using substring is that it seems more apparent what is being done.

If you replace the dashes with slashes it will parse, then you can use the date functions to get the various components (or convert to string using one of the various toString() functions).
var date = new Date( Date.parse( old.replace(/-/g,'/') ) );
alert( date.getMonth() + '/' + date.getDate() + '/' + date.getFullYear() );
This has the advantage of being able to use the date as a date for calculations, not merely doing string formatting. If string formatting is all you need AND your date strings are always valid, then using #Guffa's substr method is probably the best way to handle it.

By brute force you could do something like:
var old = '2010-02-03'.split('-');
var desired = old[1] + '/' + old[2] + '/' + old[0];
Saves the hassle of working with Date object.

Formatting the Date in JavaScript

Using newDate() function in Java script, I am able to get today's date. I am getting the date in the format 3/3/2009 (d/m/yyyy). But i actually need the date in the format 2009-03-03 (yyyy-mm-dd). Can anyone pls let me know how to format the date as i require?

You usually have to write your own function to handle the formatting of the date as javascript doesn't include nice methods to format dates in user defined ways. You can find some nice pieces of code on the net as this has been done to death, try this:
http://blog.stevenlevithan.com/archives/date-time-format
Edit: The above code seems to be really nice, and installs a cool 'format' method via the date object's prototype. I would use that one.

If you want to roll-your-own, which is not too difficult, you can use the built-in javascript Date Object methods.
For example, to get the current date in the format you want, you could do:
var myDate = new Date();
var dateStr = myDate.getFullYear +
'-' + (myDate.getMonth()+1) + '-' + myDate.getDate();
You may need to zero-pad the getDate() method if you require the two-digit format on the day.
I create a few useful js functions for date conversions and use those in my applications.

There's a very nice library to manage date in JS.
Try this.

You'll pretty much have to format it yourself, yeah.
var curDate = new Date();
var year = curDate.getFullYear();
var month = curDate.getMonth() + 1;
var date = curDate.getDate();
if (month < 10) month = "0" + month;
if (date < 10) date = "0" + date;
var dateString = year + "-" + month + "-" + date;
It's a bit long, but it'll work (:

add jquery ui plugin in your page.
function DateFormate(dateFormate, dateTime) {
return $.datepicker.formatDate(dateFormate, dateTime);
};

Just another option, which I wrote:
DP_DateExtensions Library
Not sure if it'll help, but I've found it useful in several projects.
Supports date/time formatting, date math (add/subtract date parts), date compare, date parsing, etc. It's liberally open sourced.
No reason to consider it if you're already using a framework (they're all capable), but if you just need to quickly add date manipulation to a project give it a chance.