Develop Reference

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');

Getting today's date from a specific date format in React

I would like to get today's date with the format below in React:
"2019020420"
I am able to get the current date with this function. How do I modify this such that it will give me the above date format?
getCurrentDate() {
var tempDate = new Date();
var date = tempDate.getFullYear() + '-' + (tempDate.getMonth()+1) + '-' + tempDate.getDate() +' '+ tempDate.getHours()+':'+ tempDate.getMinutes()+':'+ tempDate.getSeconds();
const currDate = date;
return currDate;
}

You can use template literals.
let formatTwoDigits = (digit) => ("0" + digit).slice(-2);
var tempDate = new Date();
var date = `${tempDate.getFullYear()}${formatTwoDigits(tempDate.getMonth()+1)}${formatTwoDigits(tempDate.getDate())}${formatTwoDigits(tempDate.getHours())}${formatTwoDigits(tempDate.getMinutes())}${formatTwoDigits(tempDate.getSeconds())}`;
console.log(date);
However, implementing date formatting by ourselves sometimes could be tedious. If you don't mind using a library, you can take a look at moment.js and its format functions. Moment.js is a commonly used JS library for parsing, manipulating, and formatting dates.

try this library for formatting date in your desired format.
https://date-fns.org/

use moment.js from https://momentjs.com/
Take a look at there first few examples for how to use it for reformatting dates.

How to get date from js in correct format? Month and days get reversed

I am calling an ajax for getting some values for editing data.
As a part of my object, I am sending the date field.
My problem is that when I receive the date value in the controller, date format is wrong - my dates and months are reversed. And because of that I can't compare them where I need to.
But my months and days are reversed. For an example , instead of 3rd October, it returnes 10th of March.
How to fix this?
I am sending the date field from js in a object like this:
ExamsDataU = {
classId: classIdValue,
date: dateValue
};
And in my controller I tried:
DateTime dateToCheck = Convert.ToDateTime(dto.Date);

The first thing you should know is date parsing with Convert.ToDateTime() depends to the current culture used in server (you may check it using CultureInfo.CurrentCulture property). You can try one of these methods to parse JS date format properly inside controller action method:
1) Using DateTime.ParseExact()/DateTime.TryParseExact() with custom format
On this way it is necessary to specify date format before parsing date:
// specify custom format
string dateFormat = "dd-MM-yyyy";
DateTime dateToCheck = DateTime.ParseExact(dto.Date, dateFormat, CultureInfo.InvariantCulture);
2) Using DateTime.ParseExact()/DateTime.TryParseExact() with ISO 8601 format
Use date: dateValue.toISOString(); to convert JS date into ISO 8601 format and then convert it:
// specify ISO format
string dateFormat = "yyyy-MM-ddTHH:mm:ss.fffZ";
DateTime dateToCheck = DateTime.ParseExact(dto.Date, dateFormat, CultureInfo.InvariantCulture, DateTimeStyles.RoundtripKind);
This way is better than the former because no need to write additional date representation code in client-side, also you can adjust date representation to local time if necessary.
Notes:
a) For specified culture, you can try CultureInfo.GetCultureInfo():
var culture = CultureInfo.GetCultureInfo(CultureInfo.CurrentCulture.Name);
DateTime dateToCheck = DateTime.ParseExact(dto.Date, dateFormat, culture);
b) You can use if condition to check if the date string is valid when using DateTime.TryParseExact():
DateTime dateToCheck;
if (DateTime.TryParseExact(dto.Date, dateFormat, CultureInfo.InvariantCulture, DateTimeStyles.None, out dateToCheck))
{
// do something
}

Try this
var date = new Date('2014-01-06');
var newDate = date.toString('dd-MM-yy');
or
var dateAr = '2014-01-06'.split('-');
var newDate = dateAr[1] + '-' + dateAr[2] + '-' + dateAr[0].slice(-2);
console.log(newDate);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

Convert Date String(yymmdd) to Date Object in JS

I have a date string in "yymmdd" format i want to convert it into date object in JS
the input string is "161208"
I have tried code below
var mydate = new Date(InputDate);
but it says invalid date.
Here is the fiddle
https://jsfiddle.net/4ry0hL4t/
the basic need is that, I have a date string in "yymmdd" format and i have to convert it to different date formats like ("yyyy/mm/dd, yy-mm-dd","yy/mm").

Check my answer.
Basically you first need to give a proper format to your string. You can either do it manually or use moment.js.
stringFormat = moment(dateObject).format("YYYY-MM-DDTHH:mm:ss");
date = new Date(stringFormat);
This is also really helpful to understand how the different string formats are compatible with different browsers.

I'm not sure if this is what you're after?
var s = '161208';
var dt = new Date('20' + s.substring(0, 2) + '-' + s.substring(2, 4) + '-' + s.substring(4));

Convert and Read JSON date type in Javascript

I have a date in the form of:
"2012-10-11T00:00:00"
The date is returned from a ASP.NET Webservice as part of a JOSN object. How can I convert this date format to a Javascript date object and also write the date as follows to the screen:
11/10/2012
Thanks

var myDate = new Date("2012-10-11T00:00:00".replace(/T/," "));
var myDateString = myDate.getDate() + "/" + (myDate.getMonth() + 1) + "/" + myDate.getFullYear()

For date conversions I use a plugin
date.js
Be sure to include all the jquery files needed, there is plenty of documentation on how to implement this
If you do not want to use a plugin check this out http://msdn.microsoft.com/en-us/library/ie/ff743760(v=vs.94).aspx
Or this overflow answer