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Compare a date in string format with todays date

I know this has been asked before but I can't get it to work due to my date format, which I can't change. Any help would be appreciated.
My date is in this format;
4/11/2017 12:30 PM.
If I inspect it in the developer tools it shows it as
4/11/2017 12:30 PM EDIT: Won't show with prepended space here
i.e. with a space in front, not sure if that's relevant.
Does anyone know if it's possible or how to compare it with today's date to see if it's in the past or future?
I've tried tinkering with the following code but can't get it to work because of the time, PM, and forward slashes.
var q = new Date();
var m = q.getMonth();
var d = q.getDate();
var y = q.getFullYear();
var date = new Date(d,m,y);
mydate=new Date('13/04/2017');
console.log(date);
console.log(mydate)
if(date>mydate)
{
alert("greater");
}
else
{
alert("smaller")
}

If you have dates that are in the same format of something like 13/04/2017, you could split the string based on the slashes and compare the values starting from the right moving left.
By this, I mean when you have your array of three values for each date, you could first compare the year, if that's the same, move on to comparing the month, if that's the same then on to comparing the day.
But if for instance one of the year's is 2018 while the other is 2016, you would immediately know that the 2018 one comes later.
var st = "19/05/2019";
var st2 = "19/05/2019";
function provideLaterDate(date1, date2) {
var splitDateDate1 = date1.split("/").reverse();
var splitDateDate2 = date2.split("/").reverse();
var laterDate = false;
splitDateDate1.forEach(function(val, idx, arr) {
if ( laterDate === false ) {
if ( val > splitDateDate2[idx] ) {
laterDate = splitDateDate1;
} else if ( val < splitDateDate2[idx]) {
laterDate = splitDateDate2;
} else {
laterDate = "Both are the same";
}
}
});
if ( /\//.test(laterDate) ) {
return laterDate.reverse().join("/");
} else {
return laterDate;
}
}
To get rid of the "time pm" part, you could simply do something like:
// Assuming your date has a structure like this: 4/11/2017 12:30 PM.
var newDate = unformattedDate.split(" ")[0];
// This will separate your date string by spaces, and since there are no spaces until after the year in your date, the 0 index will give you the date minus the time and pm portion. Please pardon the not-consistent variable names.

The problem was with the way you were constructing date. Construct date like this var mydate = new Date(2017, 04, 03); and it works.
var q = new Date();
var m = q.getMonth();
var d = q.getDate();
var y = q.getFullYear();
var date = new Date(d, m, y);
var mydate = new Date(2017, 04, 03);
console.log(date);
console.log(mydate)
if (date > mydate) {
alert("greater");
}
else {
alert("smaller")
}

You can split the date. Be aware you should contruct your date as follows:
var date = new Date(y,m,d);
Means year first, then month and finally day, as you can see under https://www.w3schools.com/jsref/jsref_obj_date.asp
You can use the following code to perform what you want:
var q = new Date();
var m = q.getMonth();
var d = q.getDate();
var y = q.getFullYear();
var date = new Date(y,m,d);
newdate = '13/04/2017'
array = newdate.split('/');
var d1 = array[0]
var m1 = array[1]-1
var y1 = array[2]
mydate = new Date(y1,m1,d1);
console.log(date);
console.log(mydate)
if(date>mydate)
{
alert("greater");
}
else
{
alert("smaller")
}
You can always check the date created is correct by using the date.toString() function. Be aware 0=January for month as you can check under https://www.w3schools.com/jsref/jsref_getmonth.asp. That's why I added the -1 for var m1.

Problem:
It's not working because you are comparing a date with an Invalid date, it will always return false.
Explanation:
And the Invalid date comes from the line new Date('13/04/2017'), because 13 is expected to be a month number and not a day which is an invalid month, because the new Date(stringDate) will be treated as a local Date and not a UTC date by the browser, and it depends on which browser you are using.
You can see in the JavaScript Date Specification that:
parsing of date strings with the Date constructor (and Date.parse, they are equivalent) is strongly discouraged due to browser differences and inconsistencies. Support for RFC 2822 format strings is by convention only. Support for ISO 8601 formats differs in that date-only strings (e.g. "1970-01-01") are treated as UTC, not local.
Demo:
So if we change new Date('13/04/2017') to new Date('04/13/2017') the code will work as expected:
var date = new Date();
var mydate = new Date('04/13/2017');
console.log(date);
console.log(mydate)
if (date > mydate) {
alert("greater");
} else {
alert("smaller")
}

if(date.getTime()>mydate.getTime()){
alert("greater");
}
else if (date.getTime()==mydate.getTime){
alert("simmilar");
else {alert("smaller");}

How to parse date string in jQuery and check if it is in the past

I need to check if the date is in the past. This is what I have so far. JSfiddle here.
var date = "09/12/2013";
var d = new Date();
var month = d.getMonth() + 1;
var day = d.getDate();
var todaysDate = +(('' + day).length < 2 ? '0' : '') + day + '/' + (('' + month).length < 2 ? '0' : '') + month + '/' + d.getFullYear();
if (date < todaysDate) {
alert("in the past");
} else {
alert("in the future");
}
Currently it is saying that the date was in the past, when it should be in the future. I know I need to parse the string as a date, but not sure how.
Help?

With that input format, you can't use a string comparison, because the least significant values are on the left. Note: I'm assuing that date is December 9th, 2013. If you're doing the American thing where it's September 12th, 2013, you'll have to adjust the indexes into parts below.
You could reverse the fields:
var date = "09/12/2013";
var parts = date.split('/');
date = parts[2] + "/" + parts[1] + "/" + parts[0];
...and then do your string comparison (being sure to construct the string for "today" in the same order — year/month/day).
If you're going to do that, you could go ahead and finish the job
var date = "09/12/2013";
var parts = date.split('/');
var date = new Date(parseInt(parts[2], 10), // year
parseInt(parts[1], 10) - 1, // month, starts with 0
parseInt(parts[0], 10)); // day
if (date < new Date()) {
// It's in the past, including one millisecond ago
}
...but of course, if you don't want the expression to be true for one millisecond ago, your string approach is fine.

var date = new Date("09/12/2013");
var d = new Date();
console.log(date>d); // true
var date = new Date("09/12/2011");
console.log(date>d); // false

JavaScript's native Date comparator only works on Date objects, whereas you are comparing Strings. You should parse date into a Date object, and then compare it with d.
//define parse(string) --> Date
if(parse(date) < new Date()) {
alert('past');
} else {
alert('future');
}

Compare dates are not returning correct results in javascript

I am comparing two dates in javascript
function checkCurrentDate(expiryDate){
//var currentDateStr=expiryDate;
var currentDate = new Date();
var month = currentDate.getMonth() + 1;
var day = currentDate.getDate();
var year = currentDate.getFullYear();
currentDate = month + "/" + day + "/" + year;
var dArr = currentDate.split("/");
currentDate = dArr[0]+ "/" +dArr[1]+ "/" +dArr[2].substring(2);
var currentExpiryDateStr = expiryDate;
if(currentExpiryDateStr == currentDate){
}
if(currentExpiryDateStr < currentDate){
alert("Expiry date is earlier than the current date.");
return false;
}
}
currently the dates are in "currentExpiryDateStr " is "11/10/12" and "currentDate" is "11/8/12" now in this condition "if(currentExpiryDateStr < currentDate)" is returning true and is entering in if condition but this condition should return false and should not enter in this if condition. It was working before but dont know why it is not working now.

The Date object will do what you want - construct one for each date, then just compare them using the usual operators.
try this..
function checkCurrentDate(expiryDate){
var currentDate = new Date(); // now date object
var currentExpiryDateStr = new Date(expiryDate); //expiry date object
if(currentExpiryDateStr == currentDate){
}
if(currentExpiryDateStr < currentDate){
alert("Expiry date is earlier than the current date.");
return false;
}
}
here is the fiddle:: http://jsfiddle.net/YFvAC/3/

var currentDate = Date.now();
if (expiryDate.getTime() < currentDate ) {
alert("Expiry date is earlier than the current date.");
return false;
}
The now() method returns the milliseconds elapsed since 1 January 1970 00:00:00 UTC up until now as a number.
The getTime() returns the Milliseconds since midnight January 1, 1970

You are comparing strings, you should be comparing date objects.
If the expriy date is '11/10/12' in the format month/day/year and that the year is a two digit year after 2000, you can convert that to a date using:
function mdyToDate(dateString) {
var b = dateString.split(/\D/);
return new Date('20' + b[2], --b[0], b[1]);
}
To test expiry, you can do something like:
function hasExpired(dateString) {
var expiryDate = mdyToDate(dateString);
var now = new Date();
return now > expiryDate;
}
So on 8-Nov-2012:
hasExpired('11/10/12'); // 10-Nov-2012 -- false
hasExpired('6/3/12'); // 03-Jun-2012 -- true
The hasExpired function can be replace with:
if (new Date() > mdyToDate(dateString)) {
// dateString has expired
}

Just add this 2 lines before your if condition
currentExpiryDateStr=Date.parse(currentExpiryDateStr);
currentDate=Date.parse(currentDate);

Date validation with JavaScript

I have a date string in this format - "DD-MM-YYYY"
this validates that successfully:
var dateFormat = /(0[1-9]|[12][0-9]|3[01])-(0[1-9]|1[012])-\d{4}/ ;
if(!startDate.match(dateFormat)){
alert("'Start Date' must be in format: DD-MM-YYYY");
return false;
I need to check that the inserted date is after today's date(or today's date).
how can i do that with JavaScript?
I've tried this:
http://www.redips.net/javascript/date-validation/
with the separator, didn't work. suggestions?

First, this is your current date in javascript:
var today = new Date();
var day = today.getDate();
var month = today.getMonth()+1; // Zero indexed
All you need to do, from here, is to compare this with your start date!
Best regards!
check this out maybe it helps to understand the date object.

Check out date.js, specifically...
http://code.google.com/p/datejs/wiki/APIDocumentation#compare
Compares the first date to the second date and returns an number
indication of their relative values. -1 = this is < date. 0 =
values are equal. 1 = this is > date.
The isAfter() and the isBefore() methods might be useful for your problem :)
Download the library here:
http://code.google.com/p/datejs/downloads/detail?name=date.js&can=2&q=
Also, its worth mentioning to checkout moment.js. I think the two libraries complement each other.

You could do this with moment.js pretty easily.
var input = moment(startDate, "DD-MM-YYYY");
if (input < moment()) {
// before today
} else {
// after today
}
We're also adding date validation pretty soon. See more info about validation here: https://github.com/timrwood/moment/pull/306

Something like this should work. Could use some cleanup, but hopefully gets the point across.
var dateFormat = /(0[1-9]|[12][0-9]|3[01])-(0[1-9]|1[012])-(\d{4})/;
var dateMatch = startDate.exec(dateFormat);
var today = new Date();
today.setHours(0); today.setMinutes(0); today.setSeconds(0); today.setMilliseconds(0);
if ((new Date(dateMatch[3], dateMatch[2] - 1, dateMatch[1])).getTime() >= today.getTime()) {
// Date is after or on today
}

You should check each date getTime() method and compare it. It's plain and simple, you don't need additional frameworks.
Here is an example that parses the dates from the strings, and then compares them:
var todayDate = "10-05-2012";​ // A sample date
var compareDate1 = "10-05-2012";
var compareDate2 = "03-05-2012";
var compareDate3 = "10-07-2012";
compareDates(todayDate, compareDate1);
compareDates(todayDate, compareDate2);
compareDates(todayDate, compareDate3);
function compareDates(date1String, date2String) {
var date1 = parseDate(date1String);
var date2 = parseDate(date2String);
if(date1.getTime() > date2.getTime()) {
alert("First date(" + date1String + ") is older than second date(" + date2String + ").");
} else if(date1.getTime() < date2.getTime()) {
alert("First date(" + date1String + ") is younger than second date(" + date2String + ").");
} else {
alert("The dates are the same day");
}
}
function parseDate(stringDateParam) {
var parsedDay = parseInt(stringDateParam.substring(0,2));
var parsedMonth = parseInt(stringDateParam.substring(3,5))-1;
var parsedYear = parseInt(stringDateParam.substring(6,10));
var parsedDate = new Date(parsedYear, parsedMonth, parsedDay, 0 , 0, 0, 0);
return parsedDate;
}
​
// Output:
//
// First check: The dates are the same day
// Second check: First date(10-05-2012) is older than second date(03-05-2012).
// Third check: First date(10-05-2012) is younger than second date(10-07-2012).
You probably already have a function that parses string to date object, and you should implement a check similar to the one in function compareDates based on getTime() function.
If you have further questions, leave a comment. Good Luck!
JSFiddle working example: click here

Thank you all!
this did the trick:
var today = new Date();
var Tday = today.getDate();
var Tmonth = today.getMonth()+1; // Zero indexed
var Tyear = today.getFullYear();
var aoDate;
var separator= '-';
aoDate = startDate.split(separator);
var month = aoDate[1] - 0;
var day = aoDate[0] - 0;
var year = aoDate[2] - 0;
if(year < Tyear){
alert("'Start Date' must be today or after today!");
return false;
}
if((year == Tyear) && (month < Tmonth)){
alert("'Start Date' must be today or after today!");
return false;
}
if((year == Tyear) && (month == Tmonth) && (day < Tday)){
alert("'Start Date' must be today or after today!");
return false;
}

Like most I was surprised a what js accepts as the constituent parts of a date. There may be holes in the code below which I would be glad to hear about but this seems to work for me. This assumes a DD/MM/YYYY HH:mm input format.
function strToDate(dtStr) {
if (!dtStr) return null
let dateParts = dtStr.split("/");
let timeParts = dateParts[2].split(" ")[1].split(":");
dateParts[2] = dateParts[2].split(" ")[0];
// month is 0-based, that's why we need dataParts[1] - 1
return dateObject = new Date(+dateParts[2], dateParts[1] - 1, +dateParts[0], timeParts[0], timeParts[1]);
}
// start of validation
var end_time = $('#tbDepartDtTm').val();
end_actual_time = strToDate(end_time);
// convert the date object back to a string in the required format
var dtString = ("0" + end_actual_time.getDate()).slice(-2) + "/" + ("0" + (end_actual_time.getMonth() + 1)).slice(-2) + "/" + end_actual_time.getFullYear() + " " + ("0" + end_actual_time.getHours()).slice(-2) + ":" + ("0" + end_actual_time.getMinutes()).slice(-2);
if (dtString != end_time) {
// if the string isn't the same as entered, it must be invalid. msg is a span element.
msg.textContent = "Depart date is not a valid date.";
return "Error";
}

javascript - get next day of a string

I've a var example = "05-10-1983"
How I can get the "next day" of the string example?
I've try to use Date object...but nothing...

This would do it for simple scenarios like the one you have:
var example = '05-10-1983';
var date = new Date();
var parts = example.split('-');
date.setFullYear(parts[2], parts[0]-1, parts[1]); // year, month (0-based), day
date.setTime(date.getTime() + 86400000);
alert(date);
Essentially, we create an empty Date object and set the year, month, and date with the setFullYear() function. We then grab the timestamp from that date using getTime() and add 1 day (86400000 milliseconds) to it and set it back to the date using the setTime() function.
If you need something more complicated than this, like support for different formats and stuff like that, you should take a look at the datejs library which does quite a bit of work for you.

You can do the following:
var nextDay;
var example = "05-10-1983";
nextDay = new Date(example);
nextDay.setDate(nextDay.getDate() + 1);
#getDate/#setDate gets/sets the current day of the month (1-31).
After the above is run, nextDay will be set to whatever tomorrow's date is. This will also rollover to the next month / year if it's the end of the month, and even handle leap years. :)

new Date(+new Date('05-10-1983'.replace(/-/g,'/')) + 24*60*60*1000)

The problem with the +86400000 approach is the potential for error when crossing a daylight savings time barrier.
For example, I'm on EST.
If I do this:
var d = new Date("11/04/2012 00:00:00");
var e = new Date(d.getTime() + 86400000);
e is going to be 11/4/2012 23:00:00
If you then extract just the date portion, you get the wrong value. I recently hit upon this issue while writing a calendar control.
this will do it better (and with a flexible offset which will let you do more than 1 day in the future):
function getTomorrow(d,offset) {
if (!offset) { offset = 1 }
return new Date(new Date().setDate(d.getDate() + offset));
}

So
var d = new Date("11/04/2012 00:00:00");
var e = new Date(d.getTime() + 86400000);
doesn't work because of daylight saving barriers. I ran into the same problem. I ended up doing something like this:
function next_day(date) {
var e = new Date(date.getTime() + 24 * 60 * 60 * 1000);
if e.getHours() != date.getHours() {
e = new Date(e.getTime() + (e.getHours() - date.getHours()) * 60 * 60 * 1000)
}
return e;
}

You can use framework called php.js. Google for it. This includes the advanced date functions and more

You can find out day index by getDay() function and create an array of days strings in following manner-
day = new Date(YourDate);
var dayArray = ["Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"];
day = dayArray[day.getDay()+1];

There are leap seconds, leap days, DST, etc., so this can be a tricky problem to solve in all cases.
In my opinion, the best way to address this (without a date library) is to take advantage of the Date constructor overflow feature[1]:
main();
function main() {
var date = uniqueDateParse( '05-10-1983' );
var newDate = nextDay( date );
print( date );
print( newDate );
}
function uniqueDateParse( string ) {
var stringArray = string.split( '-', 3 );
var month = stringArray[ 0 ],
day = stringArray[ 1 ],
year = stringArray[ 2 ];
// Per ISO 8601[2], using Pacific Daylight Time[3].
var dateString = year + '-' + month + '-' + day + 'T00:00:00-07:00';
return new Date( dateString );
}
function nextDay( date ) {
return new Date( date.getFullYear()
, date.getMonth()
, date.getDate() + 1 );
}
function print( object ) {
console.log( object );
}
Links
[1] https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#Parameters
[2] http://www.w3.org/TR/NOTE-datetime
[3] http://www.timeanddate.com/time/zones/pdt