Validating two date, one date should be greater than other in Javascript

Question

I have this two dates which I am getting through input field through javascript

var Date1 = document.nocAddition.Date1.value;
var Date2 = document.nocAddition.Date2.value;

I am trying to validate that Date 1 should always be more than date 2 and I am doing by the writing the below code:

var dateA = new Date(Date1);
var dateB = new Date(Date2);
if(Date.parse(dateA) < Date.parse(dateB)){
   alert('start is less than End');
   return false;
} else {
   alert('end is less than start');
   return false;
}

But the it is not matching the condition in loop and always alerting after else. Is there any new way to compare two dates through Javascript? Please help.

Possible duplicate of [Compare two dates with JavaScript](http://stackoverflow.com/questions/492994/compare-two-dates-with-javascript) — Mohammad, Sep 15 '16 at 08:13

score 1 · Answer 1 · answered Sep 15 '16 at 11:04

It's quite simple:

if(new Date(fit_start_time) <= new Date(fit_end_time))
{//compare end <=, not >=
    //your code here
}

Comparing 2 Date instances will work just fine. It'll just call valueOf implicitly, coercing the Date instances to integers, which can be compared using all comparison operators. Well, to be 100% accurate: the Date instances will be coerced to the Number type, since JS doesn't know of integers or floats, they're all signed 64bit IEEE 754 double precision floating point numbers.

score 0 · Answer 2 · edited Sep 20 '16 at 08:09

function compareDate(date1,date2){
    date1 = date1.split("-").reverse().join("-"); //formating 
    date2 = date2.split("-").reverse().join("-"); //formating 
    var oneDay = 24 * 60 * 60 * 1000;    
    var firstDate = new Date(date1);
    var secondDate = new Date(date2);
    return (Math.round((secondDate.getTime() - firstDate.getTime()) / (oneDay)) > 0);
}

example

// compareDate('2016-09-15','2016-09-17');

as formate

compareDate('15-11-2016','17-11-2015');

Validating two date, one date should be greater than other in Javascript

2 Answers2