Converting JavaScript ternary operations in dates to conditional statements

Question

var timeNow = new Date();
var hours = time.getHours() > 12 ? time.getHours() - 12 : time.getHours();
hours = hours < 10 ? "0" + hours : hours;

function functionHours(){
    if(hours > 12) {
        return (time.getHours()-12)
    } else {
        if(hours < 10 && hours > 12) {
            return ("0" + hours)
        } else {
            return (hours)
        } else {
            return (time.getHours())
        }
    }
}

I would to convert the ternary operations into if else statements, I've stored the statements on the functions unfortunately it returns an error unexpected token else. What I would like to do is to add 0 to the hours if the hour is 1-9 (E.g. 09, 08, 05, etc...) What seems to be the problem?

Re: the 2 else-clauses in an if-block. Not sure if this is caused by copy-pase, but my recommendation would be to always format your code with tabs(spaces!) correctly and have each logical if/else expression starting on the same line which makes spotting errors like these easy. — ReGdYN, Mar 23 '18 at 06:22
@gurvinder372 I've already figured that out...what I'm looking at is to transform the ternary operation applied on hours as function using if statements not another ternary operation. — Ricky, Mar 23 '18 at 06:29
why is hour sometimes a number (for values smaller than `10`) or a string? with the 12 hour scheme, you loose the meridian. isuggest to use a function which converts a given 24 h style to a meridian style in one function, to prevent, like in the above code to call a function over and over. — Nina Scholz, Mar 23 '18 at 06:53
Where do you set the variable `time`? Should that be `timeNow`? And the function needs to take parameters `hours` and `time`. — Barmar, Mar 23 '18 at 07:07

gurvinder372 · Answer 1 · 2018-03-23T06:53:50.470

1

Simply make it

var hours = time.getHours();
if (hours < 12)
{
   hours = ("0" + hours).slice(-2);
}

No need to check for scenario where hours is greater than 12 at all.

edited Mar 23 '18 at 06:53

answered Mar 23 '18 at 06:35

gurvinder372

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why a number as string with leading zero and then convert back to number? – Nina Scholz Mar 23 '18 at 06:47
@NinaScholz You are right. Unary `+` will remove the left padded `0` – gurvinder372 Mar 23 '18 at 06:54
actually asker needs conversion 24H -> 12h also. it can be done easily with `hours % 12` – skyboyer Mar 24 '18 at 19:40

Tim Biegeleisen · Answer 2 · 2018-03-23T06:23:24.537

0

Your logic is off, the following will never be true, because hours can't simultaneously be less than 10 and greater than 12 at the same time:

hours < 10 && hours > 12

Try this version, which is a close conversion of your original ternary expression:

function functionGetHours12(hours) {
    if (hours > 12) {
        hours = hours - 12
    }

    if (hours < 10) {
        return ("0" + hours)
    }
    else {
        return hours;
    }
}

console.log("hour 1: " + functionGetHours12(1));
console.log("hour 9: " + functionGetHours12(9));
console.log("hour 10: " + functionGetHours12(10));
console.log("hour 12: " + functionGetHours12(12));
console.log("hour 15: " + functionGetHours12(15));
console.log("hour 23: " + functionGetHours12(23));

edited Mar 23 '18 at 06:23

answered Mar 23 '18 at 06:18

Tim Biegeleisen

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it doesn't add a zero...I've already arrived on the same output (E.g. 2PM, 3PM). But what I wanted to do is with this format (E.g. 02:12:33 PM)...I already figured out the minutes, the seconds and the AM/PM...what my problem is the hours...Well the zero is actually needed at some format like digital watches right? – Ricky Mar 23 '18 at 06:28
@Ricky Then either you worded your question badly, or I misread it. From what I saw you want to get a two digit hour from 24 hour time. There are probably better ways to format timestamps in JS than this. – Tim Biegeleisen Mar 23 '18 at 06:29
@Tim...well I've already finish converting the seconds and the minutes, the only problem now is the hour...So I guess can I conclude that it is impossible to convert some ternary operations just like this one to functions with if statements? – Ricky Mar 23 '18 at 06:36
I can't really relate; AFAIK I answered the question. – Tim Biegeleisen Mar 23 '18 at 06:37

I. Ahmed · Answer 3 · 2018-03-23T06:36:03.903

0

Please check the converted ternary operator to if-else and function:

function functionHours(){
  var time = new Date();
  var hours = time.getHours() > 12 ? time.getHours() - 12 : time.getHours();
  if (time.getHours() > 12) {
    hours = time.getHours() - 12;
  }
  else {
    hours = time.getHours();
  }

  if(hours < 10) {
          return "0" + hours;
  }
  else {
          return hours;
  }
}
console.log(functionHours());

edited Mar 23 '18 at 06:36

answered Mar 23 '18 at 06:25

I. Ahmed

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@Ahmed...I've tried your suggestion and no luck...it doesn't add 0 to 2. What I wanted is this format (E.g. 02:30:20 pm). I've already figured the minutes and seconds, I just need to figure out how would I do the "hour" as 02, 03, 05, etc. – Ricky Mar 23 '18 at 06:34
Please check now. I have updated the code. – I. Ahmed Mar 23 '18 at 06:36
@Ricky, if(hours < 10 && hours > 12) was the culprit. I changed the condition, please check updated answer. – I. Ahmed Mar 23 '18 at 06:44
@Ahmed...it worked! Thank you very much for figuring it out...I've been working it out for hours already...This is exactly what I'm looking for...Converting ternary operations to a more readable form just like this - if statements inside a function...Thank you. – Ricky Mar 23 '18 at 06:46

Converting JavaScript ternary operations in dates to conditional statements

3 Answers3