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I'm trying to test to make sure a date is valid in the sense that if someone enters 2/30/2011 then it should be wrong.
How can I do this with any date?
One simple way to validate a date string is to convert to a date object and test that, e.g.
// Expect input as d/m/y
function isValidDate(s) {
var bits = s.split('/');
var d = new Date(bits[2], bits[1] - 1, bits[0]);
return d && (d.getMonth() + 1) == bits[1];
}
['0/10/2017','29/2/2016','01/02'].forEach(function(s) {
console.log(s + ' : ' + isValidDate(s))
})
When testing a Date this way, only the month needs to be tested since if the date is out of range, the month will change. Same if the month is out of range. Any year is valid.
You can also test the bits of the date string:
function isValidDate2(s) {
var bits = s.split('/');
var y = bits[2],
m = bits[1],
d = bits[0];
// Assume not leap year by default (note zero index for Jan)
var daysInMonth = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
// If evenly divisible by 4 and not evenly divisible by 100,
// or is evenly divisible by 400, then a leap year
if ((!(y % 4) && y % 100) || !(y % 400)) {
daysInMonth[1] = 29;
}
return !(/\D/.test(String(d))) && d > 0 && d <= daysInMonth[--m]
}
['0/10/2017','29/2/2016','01/02'].forEach(function(s) {
console.log(s + ' : ' + isValidDate2(s))
})
Does first function isValidDate(s) proposed by RobG will work for input string '1/2/'?
I think NOT, because the YEAR is not validated ;(
My proposition is to use improved version of this function:
//input in ISO format: yyyy-MM-dd
function DatePicker_IsValidDate(input) {
var bits = input.split('-');
var d = new Date(bits[0], bits[1] - 1, bits[2]);
return d.getFullYear() == bits[0] && (d.getMonth() + 1) == bits[1] && d.getDate() == Number(bits[2]);
}
I recommend to use moment.js. Only providing date to moment will validate it, no need to pass the dateFormat.
var date = moment("2016-10-19");
And then date.isValid() gives desired result.
Se post HERE
This solution does not address obvious date validations such as making sure date parts are integers or that date parts comply with obvious validation checks such as the day being greater than 0 and less than 32. This solution assumes that you already have all three date parts (year, month, day) and that each already passes obvious validations. Given these assumptions this method should work for simply checking if the date exists.
For example February 29, 2009 is not a real date but February 29, 2008 is. When you create a new Date object such as February 29, 2009 look what happens (Remember that months start at zero in JavaScript):
console.log(new Date(2009, 1, 29));
The above line outputs: Sun Mar 01 2009 00:00:00 GMT-0800 (PST)
Notice how the date simply gets rolled to the first day of the next month. Assuming you have the other, obvious validations in place, this information can be used to determine if a date is real with the following function (This function allows for non-zero based months for a more convenient input):
var isActualDate = function (month, day, year) {
var tempDate = new Date(year, --month, day);
return month === tempDate.getMonth();
};
This isn't a complete solution and doesn't take i18n into account but it could be made more robust.
var isDate_ = function(input) {
var status = false;
if (!input || input.length <= 0) {
status = false;
} else {
var result = new Date(input);
if (result == 'Invalid Date') {
status = false;
} else {
status = true;
}
}
return status;
}
this function returns bool value of whether the input given is a valid date or not. ex:
if(isDate_(var_date)) {
// statements if the date is valid
} else {
// statements if not valid
}
I just do a remake of RobG solution
var daysInMonth = [31,28,31,30,31,30,31,31,30,31,30,31];
var isLeap = new Date(theYear,1,29).getDate() == 29;
if (isLeap) {
daysInMonth[1] = 29;
}
return theDay <= daysInMonth[--theMonth]
This is ES6 (with let declaration).
function checkExistingDate(year, month, day){ // year, month and day should be numbers
// months are intended from 1 to 12
let months31 = [1,3,5,7,8,10,12]; // months with 31 days
let months30 = [4,6,9,11]; // months with 30 days
let months28 = [2]; // the only month with 28 days (29 if year isLeap)
let isLeap = ((year % 4 === 0) && (year % 100 !== 0)) || (year % 400 === 0);
let valid = (months31.indexOf(month)!==-1 && day <= 31) || (months30.indexOf(month)!==-1 && day <= 30) || (months28.indexOf(month)!==-1 && day <= 28) || (months28.indexOf(month)!==-1 && day <= 29 && isLeap);
return valid; // it returns true or false
}
In this case I've intended months from 1 to 12. If you prefer or use the 0-11 based model, you can just change the arrays with:
let months31 = [0,2,4,6,7,9,11];
let months30 = [3,5,8,10];
let months28 = [1];
If your date is in form dd/mm/yyyy than you can take off day, month and year function parameters, and do this to retrieve them:
let arrayWithDayMonthYear = myDateInString.split('/');
let year = parseInt(arrayWithDayMonthYear[2]);
let month = parseInt(arrayWithDayMonthYear[1]);
let day = parseInt(arrayWithDayMonthYear[0]);
My function returns true if is a valid date otherwise returns false :D
function isDate (day, month, year){
if(day == 0 ){
return false;
}
switch(month){
case 1: case 3: case 5: case 7: case 8: case 10: case 12:
if(day > 31)
return false;
return true;
case 2:
if (year % 4 == 0)
if(day > 29){
return false;
}
else{
return true;
}
if(day > 28){
return false;
}
return true;
case 4: case 6: case 9: case 11:
if(day > 30){
return false;
}
return true;
default:
return false;
}
}
console.log(isDate(30, 5, 2017));
console.log(isDate(29, 2, 2016));
console.log(isDate(29, 2, 2015));
It's unfortunate that it seems JavaScript has no simple way to validate a date string to these days. This is the simplest way I can think of to parse dates in the format "m/d/yyyy" in modern browsers (that's why it doesn't specify the radix to parseInt, since it should be 10 since ES5):
const dateValidationRegex = /^\d{1,2}\/\d{1,2}\/\d{4}$/;
function isValidDate(strDate) {
if (!dateValidationRegex.test(strDate)) return false;
const [m, d, y] = strDate.split('/').map(n => parseInt(n));
return m === new Date(y, m - 1, d).getMonth() + 1;
}
['10/30/2000abc', '10/30/2000', '1/1/1900', '02/30/2000', '1/1/1/4'].forEach(d => {
console.log(d, isValidDate(d));
});
Hi Please find the answer below.this is done by validating the date newly created
var year=2019;
var month=2;
var date=31;
var d = new Date(year, month - 1, date);
if (d.getFullYear() != year
|| d.getMonth() != (month - 1)
|| d.getDate() != date) {
alert("invalid date");
return false;
}
function isValidDate(year, month, day) {
var d = new Date(year, month - 1, day, 0, 0, 0, 0);
return (!isNaN(d) && (d.getDate() == day && d.getMonth() + 1 == month && d.getYear() == year));
}
I'm trying to test to make sure a date is valid in the sense that if someone enters 2/30/2011 then it should be wrong.
How can I do this with any date?
One simple way to validate a date string is to convert to a date object and test that, e.g.
// Expect input as d/m/y
function isValidDate(s) {
var bits = s.split('/');
var d = new Date(bits[2], bits[1] - 1, bits[0]);
return d && (d.getMonth() + 1) == bits[1];
}
['0/10/2017','29/2/2016','01/02'].forEach(function(s) {
console.log(s + ' : ' + isValidDate(s))
})
When testing a Date this way, only the month needs to be tested since if the date is out of range, the month will change. Same if the month is out of range. Any year is valid.
You can also test the bits of the date string:
function isValidDate2(s) {
var bits = s.split('/');
var y = bits[2],
m = bits[1],
d = bits[0];
// Assume not leap year by default (note zero index for Jan)
var daysInMonth = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
// If evenly divisible by 4 and not evenly divisible by 100,
// or is evenly divisible by 400, then a leap year
if ((!(y % 4) && y % 100) || !(y % 400)) {
daysInMonth[1] = 29;
}
return !(/\D/.test(String(d))) && d > 0 && d <= daysInMonth[--m]
}
['0/10/2017','29/2/2016','01/02'].forEach(function(s) {
console.log(s + ' : ' + isValidDate2(s))
})
Does first function isValidDate(s) proposed by RobG will work for input string '1/2/'?
I think NOT, because the YEAR is not validated ;(
My proposition is to use improved version of this function:
//input in ISO format: yyyy-MM-dd
function DatePicker_IsValidDate(input) {
var bits = input.split('-');
var d = new Date(bits[0], bits[1] - 1, bits[2]);
return d.getFullYear() == bits[0] && (d.getMonth() + 1) == bits[1] && d.getDate() == Number(bits[2]);
}
I recommend to use moment.js. Only providing date to moment will validate it, no need to pass the dateFormat.
var date = moment("2016-10-19");
And then date.isValid() gives desired result.
Se post HERE
This solution does not address obvious date validations such as making sure date parts are integers or that date parts comply with obvious validation checks such as the day being greater than 0 and less than 32. This solution assumes that you already have all three date parts (year, month, day) and that each already passes obvious validations. Given these assumptions this method should work for simply checking if the date exists.
For example February 29, 2009 is not a real date but February 29, 2008 is. When you create a new Date object such as February 29, 2009 look what happens (Remember that months start at zero in JavaScript):
console.log(new Date(2009, 1, 29));
The above line outputs: Sun Mar 01 2009 00:00:00 GMT-0800 (PST)
Notice how the date simply gets rolled to the first day of the next month. Assuming you have the other, obvious validations in place, this information can be used to determine if a date is real with the following function (This function allows for non-zero based months for a more convenient input):
var isActualDate = function (month, day, year) {
var tempDate = new Date(year, --month, day);
return month === tempDate.getMonth();
};
This isn't a complete solution and doesn't take i18n into account but it could be made more robust.
var isDate_ = function(input) {
var status = false;
if (!input || input.length <= 0) {
status = false;
} else {
var result = new Date(input);
if (result == 'Invalid Date') {
status = false;
} else {
status = true;
}
}
return status;
}
this function returns bool value of whether the input given is a valid date or not. ex:
if(isDate_(var_date)) {
// statements if the date is valid
} else {
// statements if not valid
}
I just do a remake of RobG solution
var daysInMonth = [31,28,31,30,31,30,31,31,30,31,30,31];
var isLeap = new Date(theYear,1,29).getDate() == 29;
if (isLeap) {
daysInMonth[1] = 29;
}
return theDay <= daysInMonth[--theMonth]
This is ES6 (with let declaration).
function checkExistingDate(year, month, day){ // year, month and day should be numbers
// months are intended from 1 to 12
let months31 = [1,3,5,7,8,10,12]; // months with 31 days
let months30 = [4,6,9,11]; // months with 30 days
let months28 = [2]; // the only month with 28 days (29 if year isLeap)
let isLeap = ((year % 4 === 0) && (year % 100 !== 0)) || (year % 400 === 0);
let valid = (months31.indexOf(month)!==-1 && day <= 31) || (months30.indexOf(month)!==-1 && day <= 30) || (months28.indexOf(month)!==-1 && day <= 28) || (months28.indexOf(month)!==-1 && day <= 29 && isLeap);
return valid; // it returns true or false
}
In this case I've intended months from 1 to 12. If you prefer or use the 0-11 based model, you can just change the arrays with:
let months31 = [0,2,4,6,7,9,11];
let months30 = [3,5,8,10];
let months28 = [1];
If your date is in form dd/mm/yyyy than you can take off day, month and year function parameters, and do this to retrieve them:
let arrayWithDayMonthYear = myDateInString.split('/');
let year = parseInt(arrayWithDayMonthYear[2]);
let month = parseInt(arrayWithDayMonthYear[1]);
let day = parseInt(arrayWithDayMonthYear[0]);
My function returns true if is a valid date otherwise returns false :D
function isDate (day, month, year){
if(day == 0 ){
return false;
}
switch(month){
case 1: case 3: case 5: case 7: case 8: case 10: case 12:
if(day > 31)
return false;
return true;
case 2:
if (year % 4 == 0)
if(day > 29){
return false;
}
else{
return true;
}
if(day > 28){
return false;
}
return true;
case 4: case 6: case 9: case 11:
if(day > 30){
return false;
}
return true;
default:
return false;
}
}
console.log(isDate(30, 5, 2017));
console.log(isDate(29, 2, 2016));
console.log(isDate(29, 2, 2015));
It's unfortunate that it seems JavaScript has no simple way to validate a date string to these days. This is the simplest way I can think of to parse dates in the format "m/d/yyyy" in modern browsers (that's why it doesn't specify the radix to parseInt, since it should be 10 since ES5):
const dateValidationRegex = /^\d{1,2}\/\d{1,2}\/\d{4}$/;
function isValidDate(strDate) {
if (!dateValidationRegex.test(strDate)) return false;
const [m, d, y] = strDate.split('/').map(n => parseInt(n));
return m === new Date(y, m - 1, d).getMonth() + 1;
}
['10/30/2000abc', '10/30/2000', '1/1/1900', '02/30/2000', '1/1/1/4'].forEach(d => {
console.log(d, isValidDate(d));
});
Hi Please find the answer below.this is done by validating the date newly created
var year=2019;
var month=2;
var date=31;
var d = new Date(year, month - 1, date);
if (d.getFullYear() != year
|| d.getMonth() != (month - 1)
|| d.getDate() != date) {
alert("invalid date");
return false;
}
function isValidDate(year, month, day) {
var d = new Date(year, month - 1, day, 0, 0, 0, 0);
return (!isNaN(d) && (d.getDate() == day && d.getMonth() + 1 == month && d.getYear() == year));
}
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 :)
Is there a fast way to validate that a date/time in this format is valid?
I would prefer not to breaking it down with substrings and rebuilding it if possible
"YYYY-MM-DD HH:MM:SS"
You could parse the date string as an ISO string (by converting the space to a "T" and appending the Zulu timezone, e.g. "2011-08-16T12:34:56Z") then compare the resulting date's ISO string to the original ISO string.
function isValidDateString(s) {
try {
var isoStr = (""+s).replace(/ /,'T') + "Z"
, newStr = new Date(isoStr).toISOString();
return isoStr.slice(0,19) == newStr.slice(0,19);
} catch (e) {
return false;
}
}
This way, if the date string has invalid format, then the string "Invalid Date" will not equal the original and if it were to roll (e.g. if the day was invalid for the month) then the string value of the parsed date will not equal the original string.
[Edit]
Note the changes to the example code required by the timezone fix.
Try a regular expression like this.
Edit: Here is the string you'll want to match against:
^([1-3][0-9]{3,3})-(0?[1-9]|1[0-2])-(0?[1-9]|[1-2][1-9]|3[0-1])\s([0-1][0-9]|2[0-4]):([0-5][0-9]):([0-5][0-9])$
You can use this regex.
/^([0-9]{4})-([0-1][0-9])-([0-3][0-9])\s([0-1][0-9]|[2][0-3]):([0-5][0-9]):([0-5][0-9])$/.test("2007-08-04 18:01:01"); //true
/^([0-9]{4})-([0-1][0-9])-([0-3][0-9])\s([0-1][0-9]|[2][0-3]):([0-5][0-9]):([0-5][0-9])$/.test("2007-08-04 18:01:0"); //false
The following code below will check to see if the date input is actually a valid date.
At first glance it looks big, but it's mostly the comments.
It requires no substrings and no regular expression.
The way JavaScript works is that, if you break down a Date object with an invalid date (04/32/2010) to it's total milliseconds and then create another Date object with those milliseconds, it will not create a Date object that displays the incorrect date (04/32/2010) it will compensate and create the proper Date (05/01/2010).
So simply, if the input is different than the new Date object, then the date is not valid.
http://jsfiddle.net/dceast/vmHjN/ - Here is an example of it on JSFiddle.
var compareDate, checkDates = false;
var validateObject = {
init: function(year, month, day) {
return this.compareDate.init(year, month, day);
},
compareDate: {
init: function(year, month, day) {
var isValid = false;
// Compensate for zero based index, if month was not
// subtracted from one 0 === Jan, 1 === Feb, 2 === Mar
month -= 1;
// Create a new date object with the selected
// year, month, and day values and retrieve the
// milliseconds from it.
var mSeconds = (new Date(year, month, day)).getTime();
var objDate = new Date();
// Set the time of the object to the milliseconds
// retrieved from the original date. This will
// convert it to a valid date.
objDate.setTime(mSeconds);
// Compare if the date has changed, if it has then
// the date is not valid
if (objDate.getFullYear() === year &&
objDate.getMonth() === month &&
objDate.getDate() === day)
{
isValid = true;
}
return isValid;
}
}
};
I did so and it worked
<html>
<head>
<title>valida data</title>
<script>
function valData(data){//dd/mm/aaaa
day = data.substring(0,2);
month = data.substring(3,5);
year = data.substring(6,10);
if( (month==01) || (month==03) || (month==05) || (month==07) || (month==08) || (month==10) || (month==12) ) {//months 31 days
if( (day < 01) || (day > 31) ){
alert('invalid date');
}
} else
if( (month==04) || (month==06) || (month==09) || (month==11) ){//months 30 days
if( (day < 01) || (day > 30) ){
alert('invalid date');
}
} else
if( (month==02) ){//February and leap year
if( (year % 4 == 0) && ( (year % 100 != 0) || (year % 400 == 0) ) ){
if( (day < 01) || (day > 29) ){
alert('invalid date');
}
} else {
if( (day < 01) || (day > 28) ){
alert('invalid date');
}
}
}
}
</script>
</head>
<body>
<form>
<input type="text" name="data" id="data" onBlur="return valData(this.value)" />
</form>
</body>
</html>
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();