Develop Reference

Javascript yyyy-mm-dd converting to incorrect date (mm/dd/yyyy)

Here is the code where the user enters a date: (it has to be a date picker on my end, but the form has to submit the date field as text – don’t ask)
On submit, I call validation logic in javascript. I’ve attached a screenshot of what it looks like when I try to enter 01/01/2001 as the users birthday. It looks like when I’m converting the value string to a Date object, it’s converting to the wrong date and time. If it would just convert correctly, I could adjust the month and day and year and build a string to send in my second object.
Attaching the picture…
I’ve messed around with UTC and timezones, but to no avail.
I need my output to be a text string "01/01/2001" which I can build as long as I have the correct date going in..but it seems to calculate wrong no matter what I try.

When you construct the Date it is assumed that the string represents a time in UTC since no timezone was provided. The string is parsed as UTC, but the Date object uses your browser's local timezone.
One way to fix that is to use getUTCDay instead of getDay. Same applies to month and year.

Using a jquery datapicker library did the trick.
function initDatePickers() {
jQuery('.om-datepicker-trigger').click(function () {
var defaultDatePickerOptions = {
showOtherMonths: true,
changeMonth: true,
changeYear: true,
defaultDate: '-45y',
dateFormat: 'mm/dd/yy',
beforeShow: function (input, inst) {
var widget = jQuery(inst).datepicker('widget');
widget.css('margin-left', jQuery(input).outerWidth() + 3 -
widget.outerWidth());
},
//buttonImage: "/img/button_calendar.png",
//buttonImageOnly: true,
showOn: "both"
};
var $input = jQuery(this).parent().find('.om-input-date').first();
if ($input.hasClass('om-min-date-today')) {
var minDateTodayOptions = defaultDatePickerOptions;
minDateTodayOptions.defaultDate = 0;
minDateTodayOptions.minDate = 0;
$input.datepicker(minDateTodayOptions);
$input.datepicker('show');
} else {
$input.datepicker(defaultDatePickerOptions);
$input.datepicker('show');
}
});
jQuery('.om-input-date').click(function () {
jQuery(this).next('.om-datepicker-trigger').trigger('click');
});
// Datepicker
// --------------------------------------------------------
jQuery('.om-input-date').keyup(function () {
var inputDOBBox = jQuery(this);
var dateValue = inputDOBBox.attr('value');
if (dateValue.length == 3 || dateValue.length == 6) {
var first = dateValue.substring(0, dateValue.length - 1);
var last = dateValue.substring(dateValue.length - 1);
if (last != "/" && last != "-") {
inputDOBBox.attr('value', first + "/" + last);
}
}
});

Convert ISO date to international date type javascript

I want to filter data by current month (maybe additionally add next month data). I don't know how to go from the beginning.
In theory I think I could compare current month and month date from my data and then to display data only if two months variables match.
I thought I should start like this:
var myDate = new Date();
var thisMonth = new Date(myDate);
thisMonth.setMonth(myDate.getMonth()+1);
var nextMonth = new Date(myDate);
nextMonth.setMonth(myDate.getMonth()+2);
Thank you in advance for any kind of help!
Additional detailed explanation:
I copied SharePoint 2013 list whose data I displayed on SharePoint site page.
In content editor web part I wrote javascript code to show that list as a table.
I have two date columns (from/until) but they are displayed in table as YYYY-MM-DD HH:MM:SS. Looks to me like ISO date format. I saw several examples how to convert in js that type of date into date type like DD.MM.YYYY. None worked for me or I didn't know how to do it correctly. So I created calculated field that will present date type as text/string, after this I managed to show date on js table the way I wanted.

You should not parse strings with the Date constructor (or Date.parse, they are equivalent for parsing) as it's largely implementation dependent and notoriously unreliable.
I have two date columns (from/until) but they are displayed in table as YYYY-MM-DD HH:MM:SS. Looks to me like ISO date format.
Almost. The extended format is YYYY-MM-SSTHH:MM:SS, the T can be replaced by a space on agreement between parties exchanging the date but it's not strictly correct. If the timezone is omitted, it's treated as a "local" date (i.e. the host timezone offset is used in calculating the moment in time that it represents).
According to ECMA-262, if the format is not correct, browsers can either:
Treat it as invalid ISO 8601 and return an invalid date
Treat it as not ISO 8601 and fall back to whatever parsing algorithm they wish to use
So given:
new Date('2017-01-01 23:12:12')
Firefox returns a Date for 1 Jan 2017 23:12:12 in the host time zone, Safari returns an invalid date. Both are consistent with the standard.
So if you need a Date object, you should parse the string manually using either a library (e.g. fecha.js or moment.js) or a simple function.
But anyway, you don't need to parse the strings to a Date to reformat the string, just use string methods and avoid Date parsing vagaries completely.
function filterCurrentMonth() {
// Create string for comparison
var d = new Date();
var currentMonth = d.getFullYear() + '-' + ('0' + (d.getMonth()+1)).slice(-2);
// Hide rows that don't have string in the first cell
var rows = document.getElementById('t0').rows;
[].forEach.call(rows, function(row) {
if (row.cells[0].textContent.indexOf(currentMonth) == -1) {
row.style.display = 'none';
} else {
row.style.display = '';
}
});
}
function filterNone() {
var rows = document.getElementById('t0').rows;
[].forEach.call(rows, function(row) {
row.style.display = '';
});
}
#t0 {
font-size: 60%;
}
<button onclick="filterCurrentMonth()">Show only current month rows</button>
<button onclick="filterNone()">Show all rows</button>
<table id="t0">
<tr><td>2017-01-01 23:12:12<tr><td>2017-02-01 23:12:12<tr><td>2017-05-01 23:12:12
<tr><td>2017-03-01 23:12:12<tr><td>2017-04-01 23:12:12<tr><td>2017-12-01 23:12:12
<tr><td>2017-10-01 23:12:12<tr><td>2017-11-01 23:12:12<tr><td>2017-06-01 23:12:12
<tr><td>2017-07-01 23:12:12<tr><td>2017-09-01 23:12:12<tr><td>2017-08-01 23:12:12
<tr><td>2017-01-01 23:12:12<tr><td>2017-02-01 23:12:12<tr><td>2017-05-01 23:12:12
<tr><td>2017-03-01 23:12:12<tr><td>2017-04-01 23:12:12<tr><td>2017-12-01 23:12:12
<tr><td>2017-10-01 23:12:12<tr><td>2017-11-01 23:12:12<tr><td>2017-06-01 23:12:12
<tr><td>2017-07-01 23:12:12<tr><td>
<!-- begin snippet: js hide: false console: true babel: false -->
23:12:122017-08-01 23:12:12
Similarly, if you want to reformat the string to be DD.MM.YYYY you can just reformat the string:
/* Format string in YYYY-MM-DD HH:mm:ss format to DD.MM.YYYY
** #param {string} s - string in YYYY-MM-DD HH:mm:ss format
** #returns {string} in DD.MM.YYYY format
*/
function formatYMDtoDMY(s) {
var b = s.split(/\D/);
return b[2] + '.' + b[1] + '.' + b[0];
}
console.log(formatYMDtoDMY('2017-10-01 23:12:12'))
Note however that dates should use unambiguous formats like DD-MMM-YYYY, e.g. 01-Jan-2017. It only takes one more line of code for that. ;-)

Don't forget, getMonth() returns a Number, from 0 to 11, representing the month,
and Date make the date as object with methods and properties
There is a lot of examples here
var date = new Date('2010-10-11 00:00:00');
var formatDate = date.getDate() + '/'
+ (date.getMonth() + 1) + '/'
+ date.getFullYear();
console.log( formatDate );
So you can always pass the date on any format but there some important moments you can read here:
Converting string to date in js

Are you asking?
I don't know how to go from the beginning.
You could get the beginning from current month and the last date of next month by following code:
<html>
<script>
var myDate = new Date();
var thisMonth = new Date(myDate.getFullYear(), myDate.getMonth(), 1);
var nextMonth = new Date(myDate.getFullYear(), myDate.getMonth() + 2, 0);
console.log("Date start: " + thisMonth);
console.log("Date end: " + nextMonth);
console.log("Formatted date start: " + formatDate(thisMonth));
console.log("Formatted date end: " + formatDate(nextMonth));
function padLeft(n){
return ("00" + n).slice(-2);
}
function formatDate(){
var d = new Date,
dformat = [ d.getFullYear(),
padLeft(d.getMonth()+1),
padLeft(d.getDate())
].join('-')+
' ' +
[ padLeft(d.getHours()),
padLeft(d.getMinutes()),
padLeft(d.getSeconds())].join(':');
return dformat
}
</script>
</html>
I hope it helps you. Bye.

(getDate() - 1) function is getting the value zero if the current date is 1

My Requirement:
I'm having to fields Start Date and End Date, If the End Date is left empty while saving the record, the End Date Field value is populated with plus 1 year based on the entered from date.
My Issue:
If the Start Date is "9/1/2016" and the End Date is Left Empty means it should automatically populate the End Date value as "8/31/2016" but it returning the End Date value as "9/0/2016" and also i'm getting the following ERROR MESSAGE
Error: JS_EXCEPTION
INVALID_FLD_VALUE You have entered an Invalid Field Value Invalid Date for the following field: custrecord_end_date
CODE:
SCRIPT : CLIENT SCRIPT, EVENT :SaveRecord
function saveRecord(scriptContext) {
var newRecord= scriptContext.currentRecord;
var fromDate = new Date(newRecord.getValue('custrecord_created_date'));
var endDate = newRecord.getValue('custrecord_end_date');
if (endDate == null || endDate == '') {
//getting plus 1 year based on the From Date
tempEndDate = addingPlusYearOfTheCurrentDate(fromDate);
//setting the value to the End Date Field
newRecord.setValue('custrecord_end_date', tempEndDate);
}
}
// Add Plus Year from the Start Date when the End Date is Empty
function addingPlusYearOfTheCurrentDate(fromDate ) {
var date = new Date();
var Month = (fromDate.getMonth() + 1);
var Dates = (fromDate.getDate() - 1);
var Year = (fromDate.getFullYear() + 1);
var last_Day = new Date(Month + '/' + Dates + '/' + Year);
log.debug('last_Day:', last_Day);
return last_Day;
}

Not sure why you expected to be able to subtract 1 from 1 and get anything other than 0, but you can solve this problem by using the Date object's setFullYear() and setDate().
function addingPlusYearOfTheCurrentDate(fromDate) {
var date = new Date(fromDate);
date.setFullYear(date.getFullYear() + 1);
date.setDate(date.getDate() - 1);
return date;
}
console.log(addingPlusYearOfTheCurrentDate(new Date(2015, 10, 1)));

You should use the method nlapiStringToDate() for string to date conversions, as NetSuite gives date field value as string, which you must convert to date, and before you set back date, you must use nlapiSetFieldValue(YOUR_FIELD_ID, nlapiStringToDate(dateObject))
Please see below on suggested usage on reading and setting date fields.
function saveRecord(scriptContext) {
var newRecord = scriptContext.currentRecord;
var fromDate = nlapiStringToDate(newRecord.getValue('custrecord_created_date'));
var endDate = nlapiStringToDate(newRecord.getValue('custrecord_end_date'));
if (endDate == null || endDate == '') {
//getting plus 1 year based on the From Date
tempEndDate = addingPlusYearOfTheCurrentDate(fromDate);
//setting the value to the End Date Field
newRecord.setValue('custrecord_end_date', nlapDateToString(tempEndDate));
}

Parsing strings with the Date constructor (and Date.parse, they are equivalent for parsing) is strongly recommended against since parsing is almost entirely implementation dependent and inconsistent. Manually parse strings with a custom function or use a library.
Adding a year to a Date is fairly simple, but it seems you want the date that is one day prior to the same date next year. So add one year then subtract one day.
// Parse m/d/y format string to a Date and validate the result
function parseMDY(s) {
var b = s.split(/\D/);
var d = new Date(b[2], --b[0], b[1]);
return d && d.getMonth() == b[0]? d : new Date(NaN);
}
// Add 1 year to a Date
function addYear(d) {
if (Object.prototype.toString.call(d) != '[object Date]') return;
d.setFullYear(d.getFullYear() + 1);
d.setDate(d.getDate() -1);
return d;
}
var d = parseMDY('9/1/2016');
console.log(d.toLocaleString())
addYear(d);
console.log(d.toLocaleString())
Note that for 29 February, adding one year gives 1 May, then subtracting one day will give 28 February.

Is this a 1.0 or 2.0 script?
NetSuite's 1.0 API offers a couple date manipulation methods that might be helpful to you here: nlapiAddMonths and nlapiAddDays, as well as the Date-String conversion methods.
Here's an example of what you could do in 1.0
// 1.0 API does not pass scriptContext to saveRecord
function saveRecord() {
// Use nlapiStringToDate instead of raw Date constructor
var fromDate = nlapiStringToDate(nlapiGetFieldValue('custrecord_created_date'));
// Instead of the full extra conditional, just use || as fallback
var endDate = nlapiStringToDate(nlapiGetFieldValue('custrecord_end_date')) ||
calculateEndDate(fromDate);
// setting the value to the End Date Field
nlapiSetFieldValue('custrecord_end_date', nlapiDateToString(endDate));
}
/** #param fromDate {Date} */
function addYear(fromDate) {
return nlapiAddMonths(fromDate, 12);
}
/** #param fromDate {Date} */
function dayBefore(fromDate) {
return nlapiAddDays(fromDate, -1);
}
/** #param startDate {Date} */
function calculateEndDate(startDate) {
// add 1 year first, then subtract one day
return dayBefore(addYear(startDate));
}
If you're using 2.0 just add a comment, and I will try to update the example if I can. If you've got any questions about how this works, feel free to let me know as well.

How to change date in text box to desired format when something changed in a dropdown

I have a form which has bunch of input text boxes with date picker (datepicker.js). When user changes value in locale dropdown, I am changing the date format and reinitializing the date picker with that local specific format. If user has already entered/selected date in the textbox and changes locale then I want that date to be automatically get converted into that desired format.
For example if user has selected the date when locale drop down shows en_US and date will be 04/30/2016, if he changes the locale drop down to en_UK then I want the date to be shown as 30/04/2016 in the text box. I tried few libraries, but none of them seems to be simple. Can we do it in JQuery or UnderscorJS or in simple javascript?
dateFormat = (currentLocale == that.defaultLocale) ? 'm/d/Y' : 'd/m/Y';
var options = {
lazyInit : false, // Lazy init to prevent a lot of instances right away
timepicker : false,
format : dateFormat,
minDate: 0,
closeOnDateSelect: true
};
$('input.datetime').datetimepicker(options);
if(currentLocale == that.defaultLocale)
$('input.datetime').attr("placeholder", "mm/dd/yyyy");
else
$('input.datetime').attr("placeholder", "dd/mm/yyyy");

Are you looking for something like this? :
function getFormattedDate(date) {
var year = date.getFullYear();
var month = (1 + date.getMonth()).toString();
month = month.length > 1 ? month : '0' + month;
var day = date.getDate().toString();
day = day.length > 1 ? day : '0' + day;
return month + '/' + day + '/' + year;
}

pre-populating date input field with Javascript

I am trying to prepopulate a date into an html "date" input field, but it ignores the values I try to pass:
<html>
...
<input id='date' type='date'>
...
</html>
<script>
...
var myDate = new Date();
$("#date").val(myDate);
...
I have also tried passing the date object as a string
var myDate = new Date().toDateString();
$("#date").val(myDate);
When I open the form, the date field is blank. If I eliminate the type="date" tag, the value shows up as a string, but then I don't have access to the datepicker. How do I pre-populate a date input and still have use of the datepicker? I'm stumped.
Thanks.

It must be set in ISO-format.
(function () {
var date = new Date().toISOString().substring(0, 10),
field = document.querySelector('#date');
field.value = date;
console.log(field.value);
})()
http://jsfiddle.net/GZ46K/

Why Not to Use toISOString()
The <input type='date'> field takes a value in ISO8601 format (reference), but you should not use the Date.prototype.toISOString() function for its value because, before outputting an ISO8601 string, it converts/represents the date/time to UTC standard time (read: changes the time zone) (reference). Unless you happen to be working in or want that time standard, you will introduce a bug where your date will sometimes, but not always, change.
Populate HTML5 Date Input from Date Object w/o Time Zone Change
The only reliable way to get a proper input value for <input type='date'> without messing with the time zone that I've seen is to manually use the date component getters. We pad each component according to the HTML date format specification (reference):
let d = new Date();
let datestring = d.getFullYear().toString().padStart(4, '0') + '-' + (d.getMonth()+1).toString().padStart(2, '0') + '-' + d.getDate().toString().padStart(2, '0');
document.getElementById('date').value = datestring;
/* Or if you want to use jQuery...
$('#date').val(datestring);
*/
<input id='date' type='date'>
Populate HTML5 Date & Time Fields from Date Object w/o Time Zone Change
This is beyond the scope of the original question, but for anyone wanting to populate both date & time HTML5 input fields from a Date object, here is what I came up with:
// Returns a 2-member array with date & time strings that can be provided to an
// HTML5 input form field of type date & time respectively. Format will be
// ['2020-12-15', '01:27:36'].
function getHTML5DateTimeStringsFromDate(d) {
// Date string
let ds = d.getFullYear().toString().padStart(4, '0') + '-' + (d.getMonth()+1).toString().padStart(2, '0') + '-' + d.getDate().toString().padStart(2, '0');
// Time string
let ts = d.getHours().toString().padStart(2, '0') + ':' + d.getMinutes().toString().padStart(2, '0') + ':' + d.getSeconds().toString().padStart(2, '0');
// Return them in array
return [ds, ts];
}
// Date object
let d = new Date();
// Get HTML5-ready value strings
let dstrings = getHTML5DateTimeStringsFromDate(d);
// Populate date & time field values
document.getElementById('date').value = dstrings[0]
document.getElementById('time').value = dstrings[1]
/* Or if you want to use jQuery...
$('#date').val(dstrings[0]);
$('#time').val(dstrings[1]);
*/
<input type='date' id='date'>
<input type='time' id='time' step="1">

Thank you j08691. That link was the answer.
To others struggling like me, when they say input is "yyyy-mm-dd" the MEAN it!
You MUST have 4 digits for the year.
You MUST have a dash and no spaces.
You MUST have 2 digits for day and month.
In my example myDate.getMonth for January would only return "1" (actually it returns "0" because for some reason javascript counts months from 0-11). To get this right I had to do the following:
var myDate, day, month, year, date;
myDate = new Date();
day = myDate.getDate();
if (day <10)
day = "0" + day;
month = myDate.getMonth() + 1;
if (month < 10)
month = "0" + month;
year = myDate.getYear();
date = year + "-" + month + "-" + day;
$("#date").val(date);
I hope this helps others not waste hours like I did testing this before October or before the 10th of the month! LOL

Here is an answer based on Robin Drexlers but in local time.
//Get the local date in ISO format
var date = new Date();
date.setMinutes(date.getMinutes() - date.getTimezoneOffset());
var datestr = date.toISOString().substring(0, 10);
//Set the field value
var field = document.querySelector('#date');
field.value = datestr;
If it's a datetime field you're modifying (as opposed to just the date) don't forget to add the time T00:00, or change the substring to 16 characters for example:
//Get the local date and time in ISO format
var date = new Date();
date.setMinutes(date.getMinutes() - date.getTimezoneOffset());
var datestr = date.toISOString().substring(0, 16);
//Set the field value
var field = document.querySelector('#datetime');
field.value = datestr;

This below code populates the local date . The accepted answer populates UTC date.
var date = new Date();
field = document.querySelector('#date-id');
var day = date.getDate();
if(day<10){ day="0"+day;}
var month = date.getMonth()+1;
if(month<10){ month="0"+month;}
field.value = date.getFullYear()+"-"+month+"-"+day;

I don't have the reputation points to comment on another answer, so I'll just add a new answer. And since I'm adding an answer, I'll give more details than I would've in a comment.
There's an easier way to zero pad than all of the juggling that everyone is doing here.
var date = new Date();
var month = ('0' + (date.getMonth() + 1)).slice(-2);
var day = ('0' + date.getDate()).slice(-2);
var year = date.getFullYear();
var htmlDate = year + '-' + month + '-' + day;
console.log("Date: " + htmlDate);
Today, the output would be
Date: 2020-01-07
The code is building a dynamic string by prepending a quoted zero, then taking the last 2 characters with slice(-2). This way, if the zero makes it 01, the last 2 are 01. If the zero makes it 011, then the last two are 11.
As for the month starting at zero silliness, you can also add 1 dynamically before prepending the zero and everything still works. You just have to do the math operation before turning it into a string.
As a side note, I've noticed that when you update a date field, you have to hide the field before setting the value and show it after setting. I don't do this often enough, so I have to re-struggle each time I need to deal with it. Hopefully this will help someone from the future.
waves to future people