How to create a date object from string in javascript

Having this string 30/11/2011. I want to convert it to date object.

Do I need to use :

Date d = new Date(2011,11,30);   /* months 1..12? */

or

Date d = new Date(2011,10,30);   /* months 0..11? */

?

var d = new Date(2011,10,30);

as months are indexed from 0 in js.

You definitely want to use the second expression since months in JS are enumerated from 0.

Also you may use Date.parse method, but it uses different date format:

var timestamp = Date.parse("11/30/2011");
var dateObject = new Date(timestamp);

The syntax is as follows:

new Date(year, month [, day, hour, minute, second, millisecond ])

so

Date d = new Date(2011,10,30);

is correct; day, hour, minute, second, millisecond are optional.

https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Date

There are multiple methods of creating date as discussed above. I would not repeat same stuff. Here is small method to convert String to Date in Java Script if that is what you are looking for,

function compareDate(str1){
// str1 format should be dd/mm/yyyy. Separator can be anything e.g. / or -. It wont effect
var dt1   = parseInt(str1.substring(0,2));
var mon1  = parseInt(str1.substring(3,5));
var yr1   = parseInt(str1.substring(6,10));
var date1 = new Date(yr1, mon1-1, dt1);
return date1;
}

Very simple:

var dt=new Date("2011/11/30");

Date should be in ISO format yyyy/MM/dd.

First extract the string like this

var dateString = str.match(/^(\d{2})\/(\d{2})\/(\d{4})$/);

Then,

var d = new Date( dateString[3], dateString[2]-1, dateString[1] );

Always, for any issue regarding the JavaScript spec in practical, I will highly recommend the Mozilla Developer Network, and their JavaScript reference.

As it states in the topic of the Date object about the argument variant you use:

new Date(year, month, day [, hour, minute, second, millisecond ])

And about the months parameter:

> month Integer value representing the month, beginning with 0 for January to 11 for December.

Clearly, then, you should use the month number 10 for November.

P.S.: The reason why I recommend the MDN is the correctness, good explanation of things, examples, and browser compatibility chart.

I can't believe javascript isn't more consistent with parsing dates. And I hear the default when there is no timezone is gonna change from UTC to local -- hope the web is prepared ;)

I prefer to let Javascript do the heavy lifting when it comes to parsing dates. However it would be nice to handle the local timezone issue fairly transparently. With both of these things in mind, here is a function to do it with the current status quo -- and when Javascript changes it will still work but then can be removed (with a little time for people to catch up with older browsers/nodejs of course).

function strToDate(dateStr)
{
    var dateTry = new Date(dateStr);

    if (!dateTry.getTime())
    {
        throw new Exception("Bad Date! dateStr: " + dateStr);
    }

    var tz = dateStr.trim().match(/(Z)|([+-](\d{2})\:?(\d{2}))$/);

    if (!tz)
    {
        var newTzOffset = dateTry.getTimezoneOffset() / 60;
        var newSignStr = (newTzOffset >= 0) ? '-' : '+';
        var newTz = newSignStr + ('0' + Math.abs(newTzOffset)).slice(-2) + ':00';

        dateStr = dateStr.trim() + newTz;
        dateTry = new Date(dateStr);

        if (!dateTry.getTime())
        {
            throw new Exception("Bad Date! dateStr: " + dateStr);
        }
    }

    return dateTry;
}

We need a date object regardless; so createone. If there is a timezone, we are done. Otherwise, create a local timezone string using the +hh:mm format (more accepted than +hhmm).