Comparing Dates of Different Formats

Question

I'm trying to write a piece of code similar to below in AngularJS:

$scope.isAfterToday= function(inputDate){
    if(inputDate > Date.now().toString()){
        return true;
    } else {
        return false;
    }
}

However, the problem is that the parameter inputDate comes in the format "2016-10-12T00:00:00" which is different than the format that comes out of the Date.now() function. Is there an easy way to convert between these two formats other than brute force of parsing out the month, day, and year from each and comparing the two?

Thank you for any help!

You can use a library like [Moment.js](http://momentjs.com/) — Roberto Linares, Oct 07 '16 at 20:50
Take a look at [the documentation](http://stackoverflow.com/documentation/javascript/265/date/1204/comparing-date-values#t=2016100721095820732) — Heretic Monkey, Oct 07 '16 at 21:10
Possible duplicate of [Compare two dates with JavaScript](http://stackoverflow.com/questions/492994/compare-two-dates-with-javascript) — Heretic Monkey, Oct 07 '16 at 21:10

LinuxDisciple · Accepted Answer · 2018-10-29T16:09:40.123

1

$scope.isAfterToday=function(inputDate){
    //First get the first time *after* today:
    var t = new Date().setHours(0,0,0,0);//0 seconds into this morning
    t.setDate(t.getDate()+1); //midnight tomorrow
    new Date(inputDate) > t );
};

No external library necessary. You can compare Date objects directly, and the Date constructor accepts a variety of date format strings as input.

For Date object comparisons, you can use common numeric comparators:

<
>
<=
>=

Don't use == though, it will compare their object references instead of their values.

edited Oct 29 '18 at 16:09

answered Oct 07 '16 at 20:59

LinuxDisciple

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"*midnight tonight*" would generally be the one that occurs at the end of the day. Setting the hours to 0 is the midnight at the start of the day, so really "midnight this morning". – RobG Oct 08 '16 at 03:33

score 0 · Answer 2 · answered Oct 07 '16 at 20:53

0

You can wrap the inputDate in standard Date object, like this:

new Date("2016-10-12T00:00:00").getTime(); // you'll get 1476230521000

And new Date().toISOString(); to reverse

answered Oct 07 '16 at 20:53

Telman

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"*you'll get 1476230521000*" only for users in the same time zone, if the string is parsed with current rules. – RobG Oct 08 '16 at 03:25

score 0 · Answer 3 · answered Oct 07 '16 at 21:02

You can use the Date object to convert your inputDate into a number of milliseconds that you can compare.

var convertedInput = new Date(inputDate);

If you need to go the other way and output something that looks nice, there's technically no formatted output. But parsing milliseconds into dates isn't all that hard!

var today = new Date();
var day = today.getDate();
var month = today.getMonth() + 1; //Month is 0-based for some reason
var year = today.getFullYear();
var datenow = year + "-" + month + "-" + day;

Comparing Dates of Different Formats

3 Answers3