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validate date to mm/dd/yyyy format in javascript

I have an MVC date field that I am trying to validate to mm/dd/yyyy format. I don't want the user to enter 1,2, or 3 digits for year. And, I want to make sure a valid date is entered. Here is the code that I am using:
<script type="text/javascript">
$(function () {
$('.datepicker').datepicker();
ForceDatePickerFormat();
});
function ForceDatePickerFormat() {
$(".datepicker").on("blur", function (e) {
var date, day, month, newYear, value, year;
value = e.target.value;
if (value.search(/(.*)\/(.*)\/(.*)/) !== -1) {
date = e.target.value.split("/");
month = date[0];
day = date[1];
year = date[2];
if (year === "") {
year = "0";
}
if (year.length < 4) {
alert ("Date year must by 4 digits");
}
}
});
}
</script>
I used "blur" because "keyup" caused a weird issue with the year when a user tried to change it. "Blur" is good except the user has to click to have the calendar go away, tab doesn't work, and clicking the date doesn't work. If the user hits return, it accepts the date without validating. I need to allow the user to manually enter the date, because they often enter dates way in the future. Does anyone have any suggestions for how to tweak this so that clicking the date closes the calendar, tab closes the calendar, and the date is still validated?

Here's the snippet you need. All you need to pass date to below function which returns true/false if the given date is valid/invalid
function validateDate(dateValue)
{
var selectedDate = dateValue;
if(selectedDate == '')
return false;
var regExp = /^(\d{1,2})(\/|-)(\d{1,2})(\/|-)(\d{4})$/; //Declare Regex
var dateArray = selectedDate.match(regExp); // is format OK?
if (dateArray == null){
return false;
}
month = dateArray[1];
day= dateArray[3];
year = dateArray[5];
if (month < 1 || month > 12){
return false;
}else if (day < 1 || day> 31){
return false;
}else if ((month==4 || month==6 || month==9 || month==11) && day ==31){
return false;
}else if (month == 2){
var isLeapYear = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
if (day> 29 || (day ==29 && !isLeapYear)){
return false
}
}
return true;
}
The above function will:
Checks for proper date format as MM/DD/YYYY.
Checks whether the given date is valid or not. Ex: April month is having only 30 days. If we specify day as 31 for the month of April then this function will validate it as invalid date.
Checks for 29th day of February. It will validate as a valid date only if the specified year is a leap year.
For more info please go through the link: http://www.j2eekart.com/2015/01/date-validation-in-javascript.html
Change your code as:
<script type="text/javascript">
$(document).ready(function(){
$('.datepicker').datepicker();
$(".datepicker").on("blur", function (e){
var isValidDate = validateDate(e.target.value);
if(!isValidDate){
alert("Please enter a valid date in MM/DD/YYYY format");
}
});
});
function validateDate(dateValue)
{
var selectedDate = dateValue;
if(selectedDate == '')
return false;
var regExp = /^(\d{1,2})(\/|-)(\d{1,2})(\/|-)(\d{4})$/; //Declare Regex
var dateArray = selectedDate.match(regExp); // is format OK?
if (dateArray == null){
return false;
}
month = dateArray[1];
day= dateArray[3];
year = dateArray[5];
if (month < 1 || month > 12){
return false;
}else if (day < 1 || day> 31){
return false;
}else if ((month==4 || month==6 || month==9 || month==11) && day ==31){
return false;
}else if (month == 2){
var isLeapYear = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
if (day> 29 || (day ==29 && !isLeapYear)){
return false
}
}
return true;
}
</script>

JSP Date validation

I have an jsp page where the user selects two dates. I need to validate this date to ensure that the 1st date is not less than today's date. This is the script I am using:
var todaysDate = new Date();
if(document.frm.rentedOnDate.value < todaysDate )
{
alert("Rented date should not be before today");
document.frm.bank.focus();
return false;
}
if(document.frm.rentedOnDate.value> document.frm.returnDate.value )
{
alert("Return date should be after rented date");
document.frm.bank.focus();
return false;
}
These are the date selection fields:
<p>Select Rental Date: <input type="date" name="rentedOnDate"> </p>
<p>Select Return Date: <input type="date" name="returnDate"> </p>
The second script function works when the user enters a return date which is before the rented date but the first function does not work. Any ideas why?

Your second test is comparing strings, so I wouldn't count on it being perfectly reliable (a preceding zero could break it for instance).
You need to convert the strings (the .value fields) to proper date objects, and then compare them. This will resolve your first check, and improve your second check.
This function will parse a date provided in the "yyyy-mm-dd" fashion (optional 2-digit year yields 20xx). null is returned for an invalid date.
function getDate(str)
{
var dateParts = /^(\d\d(?:\d\d)?)-(\d\d?)-(\d\d?)$/.exec(str);
if (dateParts === null)
{
return null;
}
var year = parseInt(dateParts[1]);
if (year < 100)
{
year += 2000;
}
var month = parseInt(dateParts[2]) - 1;
var day = parseInt(dateParts[3]);
var result = new Date(year, month, day);
return year === result.getFullYear()
&& month === result.getMonth()
&& day === result.getDate() ? result : null;
}

function validateDate(dates){
re = /^(\d{1,2})\/(\d{1,2})\/(\d{4})$/;
var days=new Array(31,28,31,30,31,30,31,31,30,31,30,31);
if(regs = dates.match(re)) {
// day value between 1 and 31
if(regs[1] < 1 || regs[1] > 31) {
return false;
}
// month value between 1 and 12
if(regs[2] < 1 || regs[2] > 12) {
return false;
}
var maxday=days[regs[2]-1];
if(regs[2]==2){
if(regs[3]%4==0){
maxday=maxday+1;
}
}
if(regs[1]>maxday){
return false;
}
return true;
} else {
return false;
}
}

How do I validate yyyy-mm-dd hh:mm:ss format

I saw this fiddle for validating mm/dd/yyyy or mm-dd-yyyy but I would like to validate yyyy-mm-dd hh:mm:ss format also how do I ensure that today is lesser than from date with the yyyy-mm-dd hh:mm:ss format?.
this is how I have initiated my date time picker..
$("#startDate, #endDate").datetimepicker({ dateFormat: 'yyyy-mm-dd hh:mm:ss'});
Please do help me to get this done.
Thanks

The date format that you have specified is ISO 8601. Most modern browsers support Date parsing of this string format. So you can do something like this.
Javascript
var iso8601 = "2013-02-01 10:00:00",
userDate = new Date(iso8601),
today = new Date(),
dateTime,
date,
time,
value;
// check is valid date
if (isNaN(userDate)) {
alert("invalid userDate");
}
// check if userDate is before today
if (userDate.getDate() < today.getDate()) {
alert("userDate is in past");
}
// check the string specifically matches "yyyy-mm-dd hh:mm:ss" and is valid
function isGregorianLeapYear(year) {
return year % 400 === 0 || year % 100 !== 0 && year % 4 === 0;
}
function daysInGregorianMonth(year, month) {
var days;
if (month == 2) {
days = 28;
if (isGregorianLeapYear(year)) {
days += 1;
}
} else {
days = 31 - ((month - 1) % 7 % 2);
}
return days;
}
if (typeof iso8601 !== "string") {
alert("not an iso8601 string");
} else {
dateTime = iso8601.split(" ");
if (dateTime.length !== 2) {
alert("missing date or time element");
} else {
date = dateTime[0].split("-");
if (date.length !== 3) {
alert("incorrect number of date elements");
} else {
value = +date[0];
if (date[0].length !== 4 || value < -9999 || value > 9999) {
alert("year value is incorrect");
}
value = +date[1];
if (date[1].length !== 2 || value < 1 || value > 12) {
alert("month value is incorrect");
}
value = +date[2];
if (date[2].length !== 2 || value < 1 || value > daysInGregorianMonth(+date[0], +date[1])) {
alert("day value is incorrect");
}
}
time = dateTime[1].split(":");
if (time.length !== 3) {
alert("incorrect number of time elements");
} else {
value = +time[0];
if (time[0].length !== 2 || value < 0 || value > 23) {
alert("hour value is incorrect");
}
value = +time[1];
if (time[1].length !== 2 || value < 0 || value > 59) {
alert("minute value is incorrect");
}
value = +time[2];
if (time[2].length !== 2 || value < 0 || value > 59) {
alert("second value is incorrect");
}
}
}
}
console.log(userDate);
console.log(today);
jsFiddle

Checking yyyy-mm-dd hh:mm:ss strings against each other is pretty easy because they're already in order; you can forget about what base the numbers are in and simply do < or > as in string comparison. This may not work with other dates.
function compISOZDate(d1, d2) { // d1 is
if (d1 < d2) return -1; // smaller
if (d1 === d2) return 0; // the same
/* else */ return 1; // bigger
}
Validating dates is a bit more complicated, because the number of days in months can change. You can ignore this fact and just test for digits, but I prefer meeting half way, introducing upper limits.
function verifyMyDate(d) {
var re = /^\d{4}-(0[1-9]|1[0-2])-([0-2]\d|3[01]) (0\d|1[01]):[0-5]\d:[0-5]\d$/;
// yyyy - MM - dd hh : mm : ss
return re.test(d);
}
So for example using it
var d1 = '2013-10-07 11:58:26',
d2 = '2012-06-14 19:22:03';
// check
if (!verifyMyDate(d1)) throw new Error('Invalid date: ' + d1);
if (!verifyMyDate(d2)) throw new Error('Invalid date: ' + d2);
// compare
compISOZDate(d1, d2); // 1, d1 is bigger than d2
// also
compISOZDate(d2, d1); // -1
compISOZDate(d1, d1); // 0
Now all that is left is to get the value from your inputs.

Change your RegExp inside the ValidateDate function to below code
function ValidateDate(dtValue)
{
var dtRegex = new RegExp(/\b\d{4}[\/-]\d{1,2}[\/-]\b\d{1,2} (0\d|1[01]):[0-5]\d:[0-5]\d$\b/);
return dtRegex.test(dtValue);
}
try this and let me know, same way u can validate the hh:mm:ss also

For 24 hour variation, instead of AM/PM, use:
regex = new RegExp(^\d{4}-(0[1-9]|1[0-2])-([0-2]\d|3[01]) (0\d|1\d|2[0-3]):[0-5]\d:[0-5]\d$);

This is mine I wrote and works fine :
function validateDate(dtValue) {
// Format expected dd/mm/aaaa or dd-mm-aaaa (French Date)
// Accept also d/m/aaaa or d-m-aaaa (ok for MySQL Database to have one number only for days and months)
// Before the insert into database I will convert to aaaa-mm-jj or aaaa-m-j
var dtRegex = new RegExp(/\b(0?[1-9]|([1-2]?[0-9]|3[0-1]))[\/-]([0]?[1-9]|1[0-2])[\/-]\b\d{4} ([0-1]?[0-9]|2[0-3]):[0-5]\d$\b/);
// Accept range => (01 to 31) (/ or -) (01 to 12) (/ or -) (4 numbers) space (00 to 23) : (00 to 59)
var bValidateDate= dtRegex.test(dtValue);
// Test if bValidateDate true, test and throw out (accepted from regex expression) :
// 30/02, 31/02, 31/04, 31/06, 31/09, 31/11
// 30-02, 31-02, 31-04, 31-06, 31-09, 31-11
// Get the 5 first characters
var sFebruary29= dtValue.substring(0, 5);
if (bValidateDate)
{
var aOfDateErrors= ["30/02", "31/02", "31/04", "31/06", "31/09", "31/11", "30-02", "31-02", "31-04", "31-06", "31-09", "31-11"];
if (aOfDateErrors.indexOf(sFebruary29) > -1)
{
bValidateDate= false;
}
}
// Then, if bValidateDate is still true (good format)
// check if the date is a leap year to accept 29/02 or 29-02
// And finally, my customer asked me to have a year between 2017 and now
if (bValidateDate)
{
// Get the year
var sYear= dtValue.substring(6, 10);
// Customer's constraints
var bYearCustomerOK= ((parseInt(sYear) >= 2017) && (parseInt(sYear) <= new Date().getFullYear()));
// I promise, this is the "last test'em all !"
var bFinalDate= (bYearCustomerOK) && (sYear % 400 === 0 || sYear % 100 !== 0 && sYear % 4 === 0) && ((sFebruary29 == "29/02") ||(sFebruary29 == "29-02"));
if (! bFinalDate)
{
bValidateDate= false;
}
}
return bValidateDate;
}
Please, let me know if you find a bad date :)

JavaScript Detecting Valid Dates

Possible Duplicate:
Detecting an “invalid date” Date instance in JavaScript
I was using the following to detect a valid date:
var text = $('#Date').val();
var date = Date.parse(text);
if (isNaN(date)) {
// Invalid date
}
But found that Date.parse thinks the following are valid dates (mm/dd/yyyy)
2/30/2011
11/31/2011
Any other way to detect invalid dates when the number of days surpasses the total number of
days in the month?
UPDATE: An even larger problem is that the jQuery validation plugin doesn't detect this as an invalid date either!
SOLUTION:
Based on #Guffa's comments I have created the following function to validate dates:
function validDate(text) {
var date = Date.parse(text);
if (isNaN(date)) {
return false;
}
var comp = text.split('/');
if (comp.length !== 3) {
return false;
}
var m = parseInt(comp[0], 10);
var d = parseInt(comp[1], 10);
var y = parseInt(comp[2], 10);
var date = new Date(y, m - 1, d);
return (date.getFullYear() == y && date.getMonth() + 1 == m && date.getDate() == d);
}

To check if a date is valid you can parse the components of the date, create a Date object from it, and check if the components in the data is the same as the parsed components. If you create a Date object from compnents that are out of range, the values will flow over to the next/previous period to create a valid date.
For example, new Date(2011,0,42) will create an object that contains the date 2/11/2011 instead of 1/42/2011.
By parsing the components instead of the full date you will also get around the problem with different date formats. My browser will for example expect a date format like y-m-d rather than d/m/y.
Example:
var text = '2/30/2011';
var comp = text.split('/');
var m = parseInt(comp[0], 10);
var d = parseInt(comp[1], 10);
var y = parseInt(comp[2], 10);
var date = new Date(y,m-1,d);
if (date.getFullYear() == y && date.getMonth() + 1 == m && date.getDate() == d) {
alert('Valid date');
} else {
alert('Invalid date');
}
Demo: http://jsfiddle.net/Guffa/UeQAK/

If your date format is fixed as M/D/YYYY, you could re-format the parsed date and see if it matches the input:
var d = new Date(Date.parse(str))
return str === (d.getMonth()+1)+'/'+d.getDate()+'/'+d.getYear();
However, that won't tolerate whitespace or zero-padded numbers.
If you don't need to keep the user's input exactly, you could just reformat the date anyway and pretend that was what they typed.
But if you can't do that either, I'd parse out the components myself using a RegExp and then compare them to values from the Date methods.

You could write a script to do this manually:
function checkDate(day, month) {
if ((month == 4 || month == 6 || month == 9 || month == 11) && day < 30) {
alert("Date is valid")
}
else if (month == 2 && day <= 28) {
alert("Date is valid")
}
else if ((month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) && day <= 31) {
alert("Date is valid")
}
else {
alert("Date is in-valid")
}
}
Of course, you would also need something to look out for leap years, but just remember that any year divisible by 4 and not by 100 is a leap year unless the first two digits of the year are divisible by 4. That should be easy to include in this function.

The example is wrong
the correct is
if ((month == 4 || month == 6 || month == 9 || month == 11) && day <= 30)
<= instead of =
But the example are great!

A simple, intrinsic way to achieve this can be:
let dateObj = document.getElementById('Date');
if (dateObj.validity.badInput) {
// show error message
}
Now some date formatting can be done, but HTML date-picker event has properties like badInput and valid to check invalid dates.

How can I determine whether a given string represents a date?

Is there an isDate function in jQuery?
It should return true if the input is a date, and false otherwise.

If you don't want to deal with external libraries, a simple javascript-only solution is:
function isDate(val) {
var d = new Date(val);
return !isNaN(d.valueOf());
}
UPDATE: !!Major Caveat!!
#BarryPicker raises a good point in the comments. JavaScript silently converts February 29 to March 1 for all non-leap years. This behavior appears to be limited strictly to days through 31 (e.g., March 32 is not converted to April 1, but June 31 is converted to July 1). Depending on your situation, this may be a limitation you can accept, but you should be aware of it:
>>> new Date('2/29/2014')
Sat Mar 01 2014 00:00:00 GMT-0500 (Eastern Standard Time)
>>> new Date('3/32/2014')
Invalid Date
>>> new Date('2/29/2015')
Sun Mar 01 2015 00:00:00 GMT-0500 (Eastern Standard Time)
>>> isDate('2/29/2014')
true // <-- no it's not true! 2/29/2014 is not a valid date!
>>> isDate('6/31/2015')
true // <-- not true again! Apparently, the crux of the problem is that it
// allows the day count to reach "31" regardless of the month..

simplest way in javascript is:
function isDate(dateVal) {
var d = new Date(dateVal);
return d.toString() === 'Invalid Date'? false: true;
}

Depending on how you're trying to implement this, you may be able to use the "validate" jQuery plugin with the date option set.

There's no built-in date functionality in jQuery core...and it doesn't really do anything directly to help with dates, so there aren't many libraries on top of it (unless they're date pickers, etc). There are several JavaScript date libraries available though, to make working with them just a bit easier.
I can't answer for sure what's best...it depends how they're entering it and what culture you're dealing with, keep in mind that different cultures are used to seeing their dates in different format, as a quick example, MM/DD/YYYY vs YYYY/MM/DD (or dozens of others).

The best way to get user date input is a date picker that only provides valid dates.
It can be done with a string, but you are liable to rile your users by demanding they use your chosen format.
You need to specify in your validator if dates precede months.
This uses a second argument to enforce the order.
With no second argument it uses the computer's default order.
// computer default date format order:
Date.ddmm= (function(){
return Date.parse('2/6/2009')> Date.parse('6/2/2009');
})()
allow month names as well as digits: '21 Jan, 2000' or 'October 21,1975'
function validay(str, order){
if(order== undefined) order= Date.ddmm? 0: 1;
var day, month, D= Date.parse(str);
if(D){
str= str.split(/\W+/);
// check for a month name first:
if(/\D/.test(str[0])) day= str[1];
else if (/\D/.test(str[1])) day= str[0];
else{
day= str[order];
month= order? 0: 1;
month= parseInt(str[month], 10) || 13;
}
try{
D= new Date(D);
if(D.getDate()== parseInt(day, 10)){
if(!month || D.getMonth()== month-1) return D;
}
}
catch(er){}
}
return false;
}

The problem is that entering in February 31st will return a valid date in JavaScript. Enter in the year, month, and day, turn it into a date, and see if that date matches what you input, instead of some day in March.
function isDate(y, m, d) {
var a = new Date(y, m-1, d);
// subtract 1 from the month since .getMonth() is zero-indexed.
if (a.getFullYear() == y && a.getMonth() == m-1 && a.getDate() == d) {
return true;
} else {
return false;
}
}
Technically, this is vanilla JavaScript, since jQuery doesn't really expand on the native Date object.

Date.parse will prb sort you out, without the need for jquery:
http://www.w3schools.com/jsref/jsref_parse.asp
Above removed after some kind soul pointed out how basic parseDate really is.
There is also a $.datepicker.parseDate( format, value, options ) utility function in the JQuery UI Datepicker plugin:
https://api.jqueryui.com/datepicker/

I arrived at this solution, made more complicated as I use the European format and javascript is clearly american!
function CheckDate()
{
var D = document.getElementById('FlightDate').value;
var values = D.split("-")
var newD = values [1] + "/" + values [0] + "/" + values[2]
var d = new Date(newD);
if(d == 'Invalid Date')document.getElementById('FlightDate').value = "";
}
Messy, but does the job.
If your users are american and put the day in the middle, (which I'll never understand!), then you can leave out the split and creation of the newD.
It is probable that I can override the default americanism in the JS by setting culture or some such, but my target audience is exclusively European so it was easier to rig it this way.
(Oh, this worked in Chrome, haven't tested it on anything else.)

If you don't want to use the jquery plugin I found the function at:
http://www.codetoad.com/forum/17_10053.asp
Works for me. The others I found don't work so well.
UPDATED:
From the cached version of the page at: http://web.archive.org/web/20120228171226/http://www.codetoad.com/forum/17_10053.asp
// ******************************************************************
// This function accepts a string variable and verifies if it is a
// proper date or not. It validates format matching either
// mm-dd-yyyy or mm/dd/yyyy. Then it checks to make sure the month
// has the proper number of days, based on which month it is.
// The function returns true if a valid date, false if not.
// ******************************************************************
function isDate(dateStr) {
var datePat = /^(\d{1,2})(\/|-)(\d{1,2})(\/|-)(\d{4})$/;
var matchArray = dateStr.match(datePat); // is the format ok?
if (matchArray == null) {
alert("Please enter date as either mm/dd/yyyy or mm-dd-yyyy.");
return false;
}
month = matchArray[1]; // p#rse date into variables
day = matchArray[3];
year = matchArray[5];
if (month < 1 || month > 12) { // check month range
alert("Month must be between 1 and 12.");
return false;
}
if (day < 1 || day > 31) {
alert("Day must be between 1 and 31.");
return false;
}
if ((month == 4 || month == 6 || month == 9 || month == 11) && day == 31) {
alert("Month " + month + " doesn`t have 31 days!")
return false;
}
if (month == 2) { // check for february 29th
var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
if (day > 29 || (day == 29 && !isleap)) {
alert("February " + year + " doesn`t have " + day + " days!");
return false;
}
}
return true; // date is valid
}

I guess you want something like this. +1 if it works for you.
HTML
Date : <input type="text" id="txtDate" /> (mm/dd/yyyy)
<br/><br/><br/>
<input type="button" value="ValidateDate" id="btnSubmit"/>
jQuery
$(function() {
$('#btnSubmit').bind('click', function(){
var txtVal = $('#txtDate').val();
if(isDate(txtVal))
alert('Valid Date');
else
alert('Invalid Date');
});
function isDate(txtDate)
{
var currVal = txtDate;
if(currVal == '')
return false;
var rxDatePattern = /^(\d{1,2})(\/|-)(\d{1,2})(\/|-)(\d{4})$/; //Declare Regex
var dtArray = currVal.match(rxDatePattern); // is format OK?
if (dtArray == null)
return false;
//Checks for mm/dd/yyyy format.
dtMonth = dtArray[1];
dtDay= dtArray[3];
dtYear = dtArray[5];
if (dtMonth < 1 || dtMonth > 12)
return false;
else if (dtDay < 1 || dtDay> 31)
return false;
else if ((dtMonth==4 || dtMonth==6 || dtMonth==9 || dtMonth==11) && dtDay ==31)
return false;
else if (dtMonth == 2)
{
var isleap = (dtYear % 4 == 0 && (dtYear % 100 != 0 || dtYear % 400 == 0));
if (dtDay> 29 || (dtDay ==29 && !isleap))
return false;
}
return true;
}
});
CSS
body{
font-family:Tahoma;
font-size : 8pt;
padding-left:10px;
}
input[type="text"]
{
font-family:Tahoma;
font-size : 8pt;
width:150px;
}
DEMO

You should use moment.js it's the best lib to handle all kind of dates.
Solution to your problem:
var inputVal = '2012-05-25';
moment(inputVal , 'YYYY-MM-DD', true).isValid();