Develop Reference

Javascript date comparison not incorporating year

I only want the date range to be selectable for future days and the first day should be before or the same day as the 2nd day to create a date range.
Input is
first date: 01/23/2020
second date: 03/19/2020
currdate: 12/11/2019
var curdate = month + "/" + day + "/" + year;
if(smsBlackoutFirstDateSelect.value > smsBlackoutSecondDateSelect.value){
alert("second date is before first date");
} else if(smsBlackoutFirstDateSelect.value <= curdate){
alert("first date is on or before today" + " " + smsBlackoutFirstDateSelect.value + " " +
smsBlackoutSecondDateSelect.value + " " + curdate);
} else {
some success function;
}
Output is :
first date is on or before today 01/23/2020 03/19/2020 12/11/2019
any idea why it isn't comparing years?

if you are referring to the comparison of curdate with smsBlackoutFirstDateSelect.value,
curdate is not a date field.
if you want date comparison to convert it to date by
var d1 = new Date(curdate);
and use it
you can refer below question
Compare two dates with JavaScript

I see that you're using a string to represent the date. This won't work well. Ideally, we should use javascript Date variables to handle the sorting as needed.
Try something like this and see how it compares.
Example:
3 numbers specify year, month, and day:
var curdate = new Date(2018, 11, 24);
I can't see how smsBlackoutFirstDateSelect is defined. It may also need to be casted to Dates() separately. See the other methods to create a Date() referenced below.
Reference: https://www.w3schools.com/js/js_dates.asp

(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.

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

Date formatting and comparing dates

I want to check to see if a date is before today. If it is then I want to display the date but not the time, if it is today then I want to display the time and not the date. The date I am checking is in the dd-mm-yyy hh:mm format and so they do not compare.
Please see what I have below so far:
var created = '25-05-2012 02:15';
var now = new Date();
if (created < now) {
created_format = [ format the date to be 25-05-2012 ]
} else {
created_format = [ format the date to be 02:15 ]
}
I have tried using now.dateFormat() and now.format() after seeing these in other examples but I get "is not a function" error messages.

Start by getting the parts of your date string:
var created = '25-05-2012 02:15';
var bits = created.split(/[-\s:]/);
var now = new Date();
// Test if it's today
if (bits[0] == now.getDate() &&
bits[1] == (now.getMonth() + 1) &&
bits[2] == now.getFullYear() ) {
// date is today, show time
} else {
// date isn't today, show date
}
Of course there are other ways, but I think the above is the easiest. e.g.
var otherDate = new Date(bits[2], bits[1] - 1, bits[0]);
now.setHours(0,0,0,0);
if (otherDate < now) {
// otherDate is before today
} else {
// otherDate is not before today
}
Similarly, once you've converted the string to a date you can use getFullYear, getMonth, getDate to compare with each other, but that's essentially the same as the first approach.

You can use getTime method and get timestamp. Then you can compare it with current date timestamp.

javascript date validation

Assume in my text box user enter like
18-06-2010 ,
Validation RULE if date is greater then current date then program should through the validation error like ,
PELASE ENTER PAST OR CURRENT DATE, DONT CHOOSE FUTURE DATE ,
Thanks

The date format you've specified is not recognized by javascript. Here's a script that makes some minor validity checking, but still some rough assumptions that the value entered conforms to the format above, and tries to construct the date string '2010/06/08' out of that.
var txtDate = document.getElementById('myTextBox').value;
var dateParts = txtDate.split('-');
if(dateParts.length != 3) {
alert('invalid date!');
return false;
}
var testDate = new Date(dateParts[2] + '/' + dateParts[1] + '/' + dateParts[0]);
if(isNaN(testDate.getDate())) {
alert('invalid date!');
return false;
}
Implement further error checking as you see fit. Once you know testDate is a date, you can compare it the current date: testDate > new Date()