jquery if hours and minutes <>

Question

Please, How can I set IF when time is < 21:30 ??

var dt = new Date();
if ((dt.getHours() <= 21) && (dt.getMinutes() <= 30)) { alert("check"); }

This not working when time is example 20:45

@pavel It dont work, look at https://jsfiddle.net/p04rjwsg/ For `20:45` - `dt.getHours() <= 21` will be true but `dt.getMinutes() <= 30` will be false — Carsten Løvbo Andersen, Mar 18 '21 at 08:26
What does Jquery have to do with this? This is vanilla javascript — Countour-Integral, Mar 18 '21 at 08:30
@pavel if dt is equal to 20:45 he want the alert to fire. but it will of course not — Carsten Løvbo Andersen, Mar 18 '21 at 08:32
@CarstenLøvboAndersen can only image your downvote was due to harcoded comparison date? — freedomn-m, Mar 18 '21 at 08:50
@freedomn-m true, i've also noticed that when I deleted the question. I know it was my mistake but hate when someone don't explain why they downvote — Carsten Løvbo Andersen, Mar 18 '21 at 09:08

score 1 · Accepted Answer · answered Mar 18 '21 at 08:35

1

You need to check two different things.

if hours <= 20, than everything is true.
if hours == 21, than check minutes.

var dt = new Date('2021/03/18 20:45:00');
if (dt.getHours() <= 20 || (dt.getHours() == 21 && dt.getMinutes() <= 30)) { 
    alert("check"); 
}

answered Mar 18 '21 at 08:35

pavel

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Looks like a serial downvoter - maybe someone doesn't like the question so they're downvoting viable answers. – freedomn-m Mar 18 '21 at 08:44
@freedomn-m: maybe... I don't play for rep, if anybody wants to downvote, he can :-) – pavel Mar 18 '21 at 08:46

score 0 · Answer 2 · answered Mar 18 '21 at 09:40

You could always take the time and convert it to minutes in the day - 1440 (60*24) so 21:30 becomes 21 * 60 + 30 = 1,290.

We can calculate the current minute value by taking the current date time Date.now() (milliseconds since 1/1/1970) mod 86,400,000 (milliseconds in a day) * further divide this by 60,000 (milliseconds in a minute).

(Date.now() % 86_400_000) / (60_000)

It is then trivial to compare these two values

const nineFortyFivePM = 21 * 60 + 30;
const currentMinutes = (Date.now() % 86_400_000) / (60_000);

console.log(`21:45 = ${nineFortyFivePM}`);
console.log(`currentMinutes = ${currentMinutes}`);
if (currentMinutes < nineFortyFivePM)
  alert('check');

jquery if hours and minutes <>

2 Answers2