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

Question

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

Answer 1

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.

Answer 2

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$);

Answer 3

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

Answer 4

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