Javascript Simple If/Else statement for time

Question

I have a task where the user can input the time (hour, minute, second) then he can give a second time (hour, minute, second) but this second time has to be in the same day as the first one and it have to be a later one. Example the user inputs 12:59:59, then 13:00:00. If its correct then it have to substract them.

I have been trying if the second hour is bigger then substract the hour, but the problem is with the minutes / seconds. I can't substract 0 from 59 or so..

    /* Első időpont
    var a = prompt("Add meg hogy hány óra van.");
    var b = prompt("Add meg hogy hány perc van.");
    var c = prompt("Add meg hogy hány másodperc van.");
// Második időpont
    var d = prompt("Adj meg egy későbbi órát.");
    var e = prompt("Add meg hogy hány perc van.");
    var f = prompt("Add meg hogy hány másodperc van.");

    if(isFinite(a) && isFinite(b) && isFinite(c)) {
        if(a > d) {
            document.write();
        }
    } else {
        document.write("Nem számot adtál meg.");
    }*/

Show what you have, and what specifically you need help with. This is quite vague as is. — Carcigenicate, Oct 30 '17 at 11:27
That input's value will be a date/datetime format and you can substract the timestamps and convert to hours and minutes and second from there. Keep in mind for future features, you should consider using a library that handles also the timezone issues(like Moment.js) — Dinca Adrian, Oct 30 '17 at 11:32
I recommend you use https://momentjs.com/. It supports subtraction and I believe it is exactly the library you need. — Milen Dobrinov, Oct 30 '17 at 11:32

lone_worrior · Answer 1 · 2017-10-30T12:17:07.497

0

Taking 01/01/2000 as date, you can do this

if(Date.parse('Sat, 01 Jan 2000 13:00:00') - Date.parse('Sat, 01 Jan 2000 12:59:59')>0)
{
   //do whatever you want
}

edited Oct 30 '17 at 12:17

answered Oct 30 '17 at 11:46

lone_worrior

232
2
15

And if `Date.parse('01/01/2000 13:00:00')` returns an invalid Date? – RobG Oct 30 '17 at 11:59
why would `Date.parse('01/01/2000 13:00:00')` return invalid date? – lone_worrior Oct 30 '17 at 12:01
Because it is not a format that is required to be parsed by [*ECMA-262*](http://ecma-international.org/ecma-262/8.0/#sec-date-time-string-format). – RobG Oct 30 '17 at 12:02
The only format supported by [*ECMA-262*](http://ecma-international.org/ecma-262/8.0/#sec-date-time-string-format) is a subset of the ISO 8601 extended format. Support for any other format is implementation dependent, see [*Why does Date.parse give incorrect results?*](https://stackoverflow.com/questions/2587345/why-does-date-parse-give-incorrect-results) – RobG Oct 30 '17 at 23:14

Javascript Simple If/Else statement for time

1 Answers1