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How to compare Current System date with with another date

I am getting date in string format from API.
End Date 2014-06-03T06:16:52. I need to write an if-else logic and compare the end date and current date.If end date is less than current date then show customer as In Active and if end date is greater than display the Customer as Active.
I have tried following logic but I am not able to understand and get today's time in string fromat.
this.endDate = this.sampleData != null ?
this.sampleData.customerStartDate : null;
this.currentDate = new Date();
var dd = this.currentDate.getDate();
var mm = this.currentDate.getMonth() + 1;
var yyyy = this.currentDate.getFullYear();
this.currentDate = new Date().toLocaleString()
console.log('End Date', this.endDate);
console.log('Current Date: ', this.currentDate);
if (this.endDate == null) {
this.customerStatus = 'Active';
} else {
this.customerStatus = 'In Active';
}
I am getting current date as Current Date: 4/2/2019, 1:23:34 AM
I want to be able to get in same format as End Date.
My main task is to compare the dates how do I achieve it ?

Ideally you want to clean up the date you're getting from an API, and convert it to a JS Date object. You can do this by keeping only the 2014-06-03T06:16:52 part, and giving it to the new Date() constructor.
You can get the current date by calling new Date() without parameters.
You can the turn the dates in to numbers by calling getTime() on each.
You can then compare the numbers.
const incoming_date = new Date('2014-06-03T06:16:52');
const current_date = new Date();
if (incoming_date.getTime() < current_date.getTime() {
// incoming_date is before current_date
} else {
// current_date is before incoming_date
}

as simple as this:
let date=new Date("2014-06-03T06:16:52")
date>new Date()

you could try to express dates in ms since the Unix Epoch with getTime() and compare them
if (currDate.getTime() > endDate.getTime()) {
// set customer to inactive
} else {
// keep customer active
}

I personally like to use moment() for javascript dates. You really just need to have it compare the same format, so you could have something like:
this.currentDate = moment().toISOString();
const dataDate = this.sampleData ? this.sampleData.customerStartDate : null;
this.endDate = moment(dataDate).toISOString();
if (this.endDate > this.currentDate) {
this.customerStatus = 'Active';
} else {
this.customerStatus = 'Inactive';
}

Find next instance of a given weekday (ie. Monday) with moment.js

I want to get the date of the next Monday or Thursday (or today if it is Mon or Thurs). As Moment.js works within the bounds of a Sunday - Saturday, I'm having to work out the current day and calculate the next Monday or Thursday based on that:
if (moment().format("dddd")=="Sunday") { var nextDay = moment().day(1); }
if (moment().format("dddd")=="Monday") { var nextDay = moment().day(1); }
if (moment().format("dddd")=="Tuesday") { var nextDay = moment().day(4); }
if (moment().format("dddd")=="Wednesday") { var nextDay = moment().day(4); }
if (moment().format("dddd")=="Thursday") { var nextDay = moment().day(4); }
if (moment().format("dddd")=="Friday") { var nextDay = moment(.day(8); }
if (moment().format("dddd")=="Saturday") { var nextDay = moment().day(8); }
This works, but surely there's a better way!

The trick here isn't in using Moment to go to a particular day from today. It's generalizing it, so you can use it with any day, regardless of where you are in the week.
First you need to know where you are in the week: moment().day(), or the slightly more predictable (in spite of locale) moment().isoWeekday(). Critically, these methods return an integer, which makes it easy to use comparison operators to determine where you are in the week, relative to your targets.
Use that to know if today's day is smaller or bigger than the day you want. If it's smaller/equal, you can simply use this week's instance of Monday or Thursday...
const dayINeed = 4; // for Thursday
const today = moment().isoWeekday();
if (today <= dayINeed) {
return moment().isoWeekday(dayINeed);
}
But, if today is bigger than the day we want, you want to use the same day of next week: "the monday of next week", regardless of where you are in the current week. In a nutshell, you want to first go into next week, using moment().add(1, 'weeks'). Once you're in next week, you can select the day you want, using moment().day(1).
Together:
const dayINeed = 4; // for Thursday
const today = moment().isoWeekday();
// if we haven't yet passed the day of the week that I need:
if (today <= dayINeed) {
// then just give me this week's instance of that day
return moment().isoWeekday(dayINeed);
} else {
// otherwise, give me *next week's* instance of that same day
return moment().add(1, 'weeks').isoWeekday(dayINeed);
}
See also https://stackoverflow.com/a/27305748/800457
EDIT: other commenters have pointed out that the OP wanted something more specific than this: the next of an array of values ("the next Monday or Thursday"), not merely the next instance of some arbitrary day. OK, cool.
The general solution is the beginning of the total solution. Instead of comparing for a single day, we're comparing to an array of days: [1,4]:
const daysINeed = [1,4]; // Monday, Thursday
// we will assume the days are in order for this demo, but inputs should be sanitized and sorted
function isThisInFuture(targetDayNum) {
// param: positive integer for weekday
// returns: matching moment or false
const todayNum = moment().isoWeekday();
if (todayNum <= targetDayNum) {
return moment().isoWeekday(targetDayNum);
}
return false;
}
function findNextInstanceInDaysArray(daysArray) {
// iterate the array of days and find all possible matches
const tests = daysINeed.map(isThisInFuture);
// select the first matching day of this week, ignoring subsequent ones, by finding the first moment object
const thisWeek = tests.find((sample) => {return sample instanceof moment});
// but if there are none, we'll return the first valid day of next week (again, assuming the days are sorted)
return thisWeek || moment().add(1, 'weeks').isoWeekday(daysINeed[0]);;
}
findNextInstanceInDaysArray(daysINeed);
I'll note that some later posters provided a very lean solution that hard-codes an array of valid numeric values. If you always expect to search the same days, and don't need to generalize for other searches, that'll be the more computationally efficient solution, although not the easiest to read, and impossible to extend.

get the next monday using moment
moment().startOf('isoWeek').add(1, 'week');

moment().day() will give you a number referring to the day_of_week.
What's even better: moment().day(1 + 7) and moment().day(4 + 7) will give you next Monday, next Thursday respectively.
See more: http://momentjs.com/docs/#/get-set/day/

The following can be used to get any next weekday date from now (or any date)
var weekDayToFind = moment().day('Monday').weekday(); //change to searched day name
var searchDate = moment(); //now or change to any date
while (searchDate.weekday() !== weekDayToFind){
searchDate.add(1, 'day');
}

Most of these answers do not address the OP's question. Andrejs Kuzmins' is the best, but I would improve on it a little more so the algorithm accounts for locale.
var nextMoOrTh = moment().isoWeekday([1,4,4,4,8,8,8][moment().isoWeekday()-1]);

Here's a solution to find the next Monday, or today if it is Monday:
const dayOfWeek = moment().day('monday').hour(0).minute(0).second(0);
const endOfToday = moment().hour(23).minute(59).second(59);
if(dayOfWeek.isBefore(endOfToday)) {
dayOfWeek.add(1, 'weeks');
}

Next Monday or any other day
moment().startOf('isoWeek').add(1, 'week').day("monday");

IMHO more elegant way:
var setDays = [ 1, 1, 4, 4, 4, 8, 8 ],
nextDay = moment().day( setDays[moment().day()] );

Here's e.g. next Monday:
var chosenWeekday = 1 // Monday
var nextChosenWeekday = chosenWeekday < moment().weekday() ? moment().weekday(chosenWeekday + 7) : moment().weekday(chosenWeekday)

The idea is similar to the one of XML, but avoids the if / else statement by simply adding the missing days to the current day.
const desiredWeekday = 4; // Thursday
const currentWeekday = moment().isoWeekday();
const missingDays = ((desiredWeekday - currentWeekday) + 7) % 7;
const nextThursday = moment().add(missingDays, "days");
We only go "to the future" by ensuring that the days added are between 0 and 6.

Function to iterate over an array of dates produces unexpected results

I have a CloudCode function that is called from my iOS app. The function is supposed to create a "checkin" record and return a string to represent the last 30 days of check-ins and missed days.
The strange thing is that sometimes I get the expected results and sometimes I do not. It makes me think that there is some issue with the may I am using timezones - since that could result in a different set of "days in the past" depending on what time I run this function and what time of day I checked-in in the past. But I'm baffled and could use some help here.
It's also confusing me that I do not see all of my console.log() results appear in the parse log. Is that normal?? For example, in the for loop, I can uncomment the console.log entry and call the function but I will not see all of the days in the past listed - but they are included in the final array and text string.
Here is my complete function. Any help and suggestions are appreciated.
/* Function for recording a daily check in
*
* Calculates the number of days missed and updates the string used to display the check-in pattern.
* If no days missed then we increment the current count
*
* Input:
* "promiseId" : objectID,
* "timeZoneDifference" : String +07:00
*
* Output:
* JSON String eg. {"count":6,"string":"000000000000001111101010111111"}
*
*/
Parse.Cloud.define("dailyCheckIn", function(request, response) {
var promiseId = request.params.promiseId;
var timeZoneDifference = request.params.timeZoneDifference;
var currentUser = Parse.User.current();
if (currentUser === undefined) {
response.error("You must be logged in.");
}
if (timeZoneDifference === undefined || timeZoneDifference === "") {
//console.log("timeZoneDifference missing. Set to -07:00");
timeZoneDifference = '' + '-07:00'; // PacificTime as string
}
var moment = require('cloud/libs/moment.js');
// Query for the Promise
var Promise = Parse.Object.extend("Promise");
var queryforPromise = new Parse.Query(Promise);
queryforPromise.get(promiseId, {
success: function(promis) {
// Initialize
var dinarowString = "";
var dinarowCount = 0;
// Last Check In date from database (UTC)
var lastCheckInUTC = promis.get("lastCheckIn");
if (lastCheckInUTC === undefined) {
lastCheckInUTC = new Date(2015, 1, 1);
}
// Use moment() to convert lastCheckInUTC to local timezone
var lastCheckInLocalized = moment(lastCheckInUTC.toString()).utcOffset(timeZoneDifference);
//console.log('lastCheckIn: ' + lastCheckInUTC.toString());
//console.log('lastCheckInLocalized: ' + lastCheckInLocalized.format());
// Use moment() to get "now" in UTC timezone
var today = moment().utc(); // new Date();
//console.log('today: ' + today.format());
// Use moment() to get "now" in local timezone
var todayLocalized = today.utcOffset(timeZoneDifference);
//console.log('todayLocalized: ' + todayLocalized.format());
// 30 days in the past
var thirtydaysago = moment().utc().subtract(30, 'days');
//console.log("thirtydaysago = " + thirtydaysago.format());
// 30 days in the past in local timezone
var thirtydaysagoLocalized = thirtydaysago.utcOffset(timeZoneDifference);
//console.log('thirtydaysagoLocalized: ' + thirtydaysagoLocalized.format());
// Calculate the number of days since last time user checked in
var dayssincelastcheckin = todayLocalized.diff(lastCheckInLocalized, 'days');
//console.log("Last check-in was " + dayssincelastcheckin + " days ago");
// Function takes an array of Parse.Objects of type Checkin
// itterate over the array to get a an array of days in the past as numnber
// generate a string of 1 and 0 for the past 30 days where 1 is a day user checked in
function dinarowStringFromCheckins(checkins) {
var days_array = [];
var dinarowstring = "";
// Create an array entry for every day that we checked in (daysago)
    for (var i = 0; i < checkins.length; i++) {
var checkinDaylocalized = moment(checkins[i].get("checkInDate")).utcOffset(timeZoneDifference);
var daysago = todayLocalized.diff(checkinDaylocalized, 'days');
// console.log("daysago = " + daysago);
days_array.push(daysago);
}
console.log("days_array = " + days_array);
// Build the string with 30 day of hits "1" and misses "0" with today on the right
    for (var c = 29; c >= 0; c--) {
if (days_array.indexOf(c) != -1) {
//console.log("days ago (c) = " + c + "-> match found");
dinarowstring += "1";
} else {
dinarowstring += "0";
}
}
return dinarowstring;
}
// Define ACL for new Checkin object
var checkinACL = new Parse.ACL();
checkinACL.setPublicReadAccess(false);
checkinACL.setReadAccess(currentUser, true);
checkinACL.setWriteAccess(currentUser, true);
// Create a new entry in the Checkin table
var Checkin = Parse.Object.extend("Checkin");
var checkin = new Checkin();
checkin.set("User", currentUser);
checkin.set("refPromise", promis);
checkin.set("checkInDate", today.toDate());
checkin.setACL(checkinACL);
checkin.save().then(function() {
// Query Checkins
var Checkin = Parse.Object.extend("Checkin");
var queryforCheckin = new Parse.Query(Checkin);
queryforCheckin.equalTo("refPromise", promis);
queryforCheckin.greaterThanOrEqualTo("checkInDate", thirtydaysago.toDate());
queryforCheckin.descending("checkInDate");
queryforCheckin.find().then(function(results) {
var dinarowString = "000000000000000000000000000000";
var dinarowCount = 0;
if (results.length > 0) {
dinarowString = dinarowStringFromCheckins(results);
dinarowIndex = dinarowString.lastIndexOf("0");
if (dinarowIndex === -1) { // Checked in every day in the month!
// TODO
// If the user has checked in every day this month then we need to calculate the
// correct streak count in a different way
dinarowString = "111111111111111111111111111111";
dinarowCount = 999;
} else {
dinarowCount = 29 - dinarowIndex;
}
}
// Update the promise with new value and save
promis.set("dinarowString", dinarowString);
promis.set("dinarowCount", dinarowCount);
promis.set("lastCheckIn", today.toDate());
promis.save().then(function() {
response.success(JSON.stringify({
count: dinarowCount,
string: dinarowString
}));
});
}, function(reason) {
console.log("Checkin query unsuccessful:" + reason.code + " " + reason.message);
response.error("Something went wrong");
});
}); // save.then
},
error: function(object, error) {
console.error("dailyCheckIn failed: " + error);
response.error("Unable to check-in. Try again later.");
}
});
});

There's too much going on in your question to answer adequately, but I will be nice and at least point out a few errors that you should look into:
You take input in terms of a fixed offset, but then you are doing operations that subtract 30 days. It's entirely possible that you will cross a daylight saving time boundary, in which case the offset will have changed.
See "Time Zone != Offset" in the timezone tag wiki. In moment, you can use time zones names like "America/Los_Angeles" with the moment-timezone add-on.
From your example, I'm not even sure if time zone even matters or not for your use case.
You should not convert the Date to a string just to parse it again. Moment can accept a Date object, assuming the Date object was created correctly.
moment(lastCheckInUTC.toString()).utcOffset(timeZoneDifference)
becomes
moment(lastCheckInUTC).utcOffset(timeZoneDifference)
Since Date.toString() returns a locale-specific, implementation-specific format, you'll also see you have a warning in the debug console from moment.
As for the rest, we can't run your program and reproduce the results, so there's not much we can do to help. You need to start by debugging your own program, and then try to reproduce your error in a Minimal, Complete, and Verifiable example. Chances are, you'll solve your own problem along the way. If not, then you will have something in a better state to share with us.

I am answering my own question as I have found the solution.
I had two questions. The first was "why do I get unexpected (incorrect) results" and I suspected that it was related to the way I am using timezones. I would see different results from day to day depending on what time I check in.
The problem is actually related to the way that moment().diff() works. Diff does not calculate "days" the way I expected it to. If I compare 2am today with 11pm yesterday diff will say 0 days because it is less than 24 hours diff. If I compare 1am on Thursday with 8pm on the previous Monday, diff will report 2 days - not 3 as I expected. It's a precision issue. Diff thinks 2.4 days is 2 days ago. But it is more than 2 therefor it is 3 days ago.
We found that the easiest solution is to compare the two dates at midnight rather than at the actual time of day that is recorded in the database. This yields correct results for days. The rest of the code is working fine.
//Find start time of today's day
var todayLocalizedStart = todayLocalized.startOf('day');
    for (var i = 0; i < checkins.length; i++) {
var checkinDaylocalized = moment(checkins[i].get("checkInDate")).utcOffset(timeZoneDifference);
//Find start time of checkIn day
var checkinDaylocalizedStart = checkinDaylocalized.startOf('day');
//Find number of days
var daysago = todayLocalizedStart.diff(checkinDaylocalizedStart, 'days');
// console.log("daysago = " + daysago);
days_array.push(daysago);
}
The second question I had was "is it normal to not see every console.log at runtime". I've talked with other Parse.com users and they report that Parse is inconsistent in logging. I was spending a lot of time debugging "problems" that were simply Parse not logging correctly.
Thanks to everyone that contributed to the answer.
I did make one other change - but it was not a bug. I replaced the query limit from 30 days in the past to simply "30". It's just a bit simpler with one less calculation.

How to get current date without time?

I'm trying to get the current date without the time and store it in a variable, within JavaScript. It needs to be without time as I'm converting it to an epoch date, with which I will use to measure the past 24 hours (if date is within 24 hours then it will be displayed). The problem is that with the added time, it doesn't match as within the last 24 hours.
e.g. it returns the date as the following when converted to epoch: 1408704590485
I want it to be like 1408662000000
I'm not to sure how to do this.
Code - How the current days epoch date is currently being stored -
var epochLoggingFrom;
var epochLoggingTo;
$(document).ready(function () {
epochLoggingFrom = dateToEpoch(new Date());
epochLoggingTo = dateToEpoch(new Date());
}
dateToEpoch function -
function dateToEpoch(thedate) {
return thedate.getTime();
}

Try this:
function dateToEpoch(thedate) {
var time = thedate.getTime();
return time - (time % 86400000);
}
or this:
function dateToEpoch2(thedate) {
return thedate.setHours(0,0,0,0);
}
Example : http://jsfiddle.net/chns490n/1/
Reference: (Number) Date.prototype.setHours(hour, min, sec, millisec)

Try this:
var nowDate = new Date();
var date = nowDate.getFullYear()+'/'+(nowDate.getMonth()+1)+'/'+nowDate.getDate();
Note: Adjust format as you want, like reorder day, month, year, remove '/' and get combined date etc.

or use this:
dateToEpoch(new Date().toLocaleDateString())

I tried using javascript. this method returns the current date in "DD/MM/YYYY" format.
getCurrentDate() {
const t = new Date();
const date = ('0' + t.getDate()).slice(-2);
const month = ('0' + (t.getMonth() + 1)).slice(-2);
const year = t.getFullYear();
return `${date}/${month}/${year}`;
}

javascript date validation is not working for today date

I have got below java script code that will validates date range ... when the user entered the today date or any future dates I have set IsValid to true and then will do the save operation ....
for that purpose I have written below code ..
function Save(e) {
var popupNotification = $("#popupNotification").data("kendoNotification");
var container = e.container;
var model = e.model;
var isValid = true;
var compareDate = e.model.DeliveryDate;
alert(compareDate);
var todayDate = new Date();
var compareDateModified = new Date(compareDate)
alert(compareDateModified);
if (compareDateModified > todayDate || compareDateModified === todayDate) {
isValid = true;
}
else
isValid = false;
e.preventDefault();
if (isValid == false)
{
popupNotification.show("Delivery Date should be today date or Greater", "error");
}
$('#Previous').show();
$('#Next').show();
}
Its working fine when I give the future dates but its not working for today date. I also need to check the today's date. I am not able to figure it out the error alert when I try to enter to the today date .

You are comparing two objects of the same type, but different objects, so that will always result in 'unequal'
If you use date.getTime() you will get better results in your comparison - but only if the time component is the same of course.

Think of the Date object like a timestamp. It is based on the unix-style of timestamps (the amount of seconds since 1st January, 1970) so the Date object isn't the day, it is the Date AND the Time.
What you're comparing is the times as well, which could get a little iffy. If only days matter, try using:
fullCompareDate = compareDateModified.getFullYear() + "/" + compareDateModified.getMonth() + "/" + compareDateModified.getDate();
fullTodayDate= todayDate.getFullYear() + "/" + todayDate.getMonth() + "/" + todayDate.getDate();
if(compareDateModified>todayDate||fullCompareDate==fullTodayDate)
{
//Do something
}
This will compare the date and time to make sure they are greater OR check the current date with the compare date (as strings)
Another solution is to blank out the times on both dates:
compareDateModified.setHours(0,0,0,0);
todayDate.setHours(0,0,0,0);
if(compareDateModified>=todayDate)
{
//Do something
}

You are comparing the compareDateModified to todayDate on the millisecond level. To compare at the day level:
var todayDate = new Date();
todayDate.setHours(0,0,0,0);
//you may also have to truncate the compareDateModified to the first
//second of the day depending on how you setup compareDate
if (compareDateModified >= todayDate) {
isValid = true;
}