Force displaying am/pm for times in the en-GB locale?

[mjb8086]

Hi, using Luxon to pretty print ISO 8601 dates in my application.

I have tried both .toLocaleString(DateTime.DATETIME_MED) and .toFormat("DD t"). While both options give the date correctly, e.g. as 15 May 2024 the time is given in 24 hours. In my locale (GB) it is more common to refer to the time as am/pm. I can see from the dt.locale property the locale is en-GB. Yet even when I use the explicit format sting for 12 hour time, 24 hour time is all I get.

How can I force printing of 12 hour time? I'd like this to be at least an option in my application.

Best, MJB

[icambron]

Sure:

DateTime
     .now()
     .setLocale("en-GB")
     .toLocaleString({...DateTime.DATETIME_MED, "hourCycle": "h11"}) // => '15 May 2024, 1:40 pm'

The argument to toLocaleString() is ultimately passed to the Intl.DateTimeFormat constructor and thus supports everything that does. DateTime.DATETIME_MED is just a precanned object containing formatting options. So you can just glom on extra options, as in my example.

Note that you have to override it not because of anything about DATETIME_MED but actually because of the en-GB locale, which does specify 24-hour time. In my locale ,en-US, there's no debate and we always use 12-hour time, so the locale works like that by default. The UK seems to be a bit of an in-betweener on this with official stuff in 24-hour time and informal stuff in am/pm, which puts the ICU folks in a bind about what to make the locale do.

[mjb8086]

@icambron Thanks for the swift reply, that got me sorted. Given that we also purchase fuel by the litre while measuring fuel efficiency in miles per gallon, I can understand the ICU's predicament.