datepicker date off by one day

The date returned by date picker is off by one day. Is it a problem in my code or is it a bug?

The date sent to date_picker is 2012-03-21. The date returned by datepicker is Tue Mar 20 2012.

    var end_date = end_calendar.getFormatedDate("%Y-%m-%d");
    end_date = $.datepicker.formatDate('D M dd yy', new Date(end_date));

Solution 1:

It is not the datepicker,

console.log(new Date('2012-03-21')); //prints Tue Mar 20 2012 20:00:00 GMT-0400 (Eastern Daylight Time)

The Javascript Date object can accept one of the following syntax as below,

1. new Date()
2. new Date(milliseconds)
3. new Date(dateString)
4. new Date(year, month, day [, hour, minute, second, millisecond ])

So in your case it is going to call the dateString and parse. So try appending the time as below,

new Date ('2012-03-21T00:00:00') //should return you Wed Mar 21 2012

DEMO

or Better to use as below,

new Date (2012, 2, 21). 

year - Integer value representing the year. For compatibility (in order to avoid the Y2K problem), you should always specify the year in full; use 1998, rather than 98.

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

day - Integer value representing the day of the month (1-31).

Solution 2:

Seems to be a bug. If the string sent to Date() is formatted as 2012/03/21 instead of 2012-03-21. The date seems right.