JavaScript Date getTime() inconsistent

Question

I'm trying to implement a parser for the tablesorter plugin for jQuery and I have this strange behaviour with the getTime() value for dates. The following code:

var dateOne = '03/04/2010';
var dateTwo = '28/10/2008';
var dateOneTime = new Date(dateOne).getTime();
var dateTwoTime = new Date(dateTwo).getTime();
var diff = dateOneTime - dateTwoTime;

alert('dateOneTime: ' + dateOneTime + '\ndateOne: ' + dateOne + '\nDateTwoTime: ' + dateTwoTime + '\ndateTwo : ' + dateTwo + '\none - two: ' + diff);

Gives a getTime() result for the 2010 date as 1267 billion or so, and for the 2008 date 1271 billion. Therefore subtracting dateTwo from dateOne gives a negative number. Why is this? Surely the dateTwo value, being in 2008, should be smaller?

Avoid using the string constructor altogether if possible. See http://stackoverflow.com/questions/163563/javascript-date-constructor-doesnt-work — Bryan Menard, Sep 01 '11 at 17:17

score 4 · Accepted Answer · answered Sep 01 '11 at 17:13

4

Date expects MM/DD/YYYY

You are passing in DD/MM/YYYY

answered Sep 01 '11 at 17:13

epascarello

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Yes. This is it. I am an idiot. (I have to wait 10 minutes before I can accept your answer). – Robert Sep 01 '11 at 17:16

score 1 · Answer 2 · answered Sep 01 '11 at 17:14

1

By default, the format is mm/dd/yyyy. Thus, 28/10/2008 is being interpreted as 04/10/2010.

answered Sep 01 '11 at 17:14

Briguy37

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score 1 · Answer 3 · answered Sep 01 '11 at 17:14

1

When you initialize a date in JS via a string, it should be an RFC1123-compliant format - yours aren't.

answered Sep 01 '11 at 17:14

Marc B

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score 0 · Answer 4 · answered Sep 01 '11 at 17:16

0

new Date(dateTwo) is being interpreted incorrectly as April 10 2010 because the Date constructor is expecting MM/DD/YYYY instead of the DD/MM/YYYY you are passing.

try

var dateOne = '04/03/2010';
var dateTwo = '10/28/2008';

answered Sep 01 '11 at 17:16

Hyangelo

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JavaScript Date getTime() inconsistent

4 Answers4