Question

I have a very weird problem with javascript’s getDate function. At the start of some function, i’ve created a Date object using:

var day = new Date(date);  

in which date is a unix timestamp.

I dont change the day object, but after a while I try to get the day of the month of this object, but day.getDate() keeps giving me the wrong value.

For example:

alert(day.getTime() + "-" + day.getDate() + "-"+ day.getMonth() +"-" + day.getFullYear() + "-" + day.getHours() + "-" + day.getMinutes() + "-" + day.getSeconds());  

gives me the following result: 1290297600-15-0-1970-23-24-57

and at some other point the result is: 1290384000-15-0-1970-23-26-24

And this is the weird part, if you lookup the unixtimestamp 1290297600 you’ll see that that’s the timestamp for the 21st of november 2010 at 00:00:00 gmt (1290384000 is the next day, same time)
The timestamps are correct, but i cant make sense of the dates it gives me.
This happens to me in any browser.

What am i doing wrong?

Answer 1

The issue here is that the Date object in JavaScript doesn’t take the Unix timestamp (seconds since the epoch), it actually takes the milliseconds since the epoch. If you just multiply your date variable by 1000 then you get the correct output.

Example here