Migrate from deprecated strftime to IntlDateFormatter

[nielsrune]

What are the changes about?

Since PHP 8.1 (November 2021) strftime has been deprecated and will be removed in the future.

This edit replaces all calls to that function with IntlDateFormatter::format()

Note that this requires the Intl extension which may not be installed by default.

The custom function periodeoverskrifter() has been greatly reduced, since it was never called with a non-default value to $periode_laengde="regnskabsmaaned"

Further relevant info:

• strftime manual
• IntlDateFormatter::format() manual
• PHP.watch article

Have you checked the following?

• I have updated relevant documentation at https://github.com/DANOSOFT/saldi/wiki
• I have checked that i am not linking to any external resources such as external style- or javascript-files, that could compomise stabilaty
• I have read and understood the developer guidelines
  https://docs.google.com/document/d/1GOmomtvKf21OV2VWNOIPweDi4gJHpMCK5qXzrPrypUc/edit?usp=sharing

[logicguy1]

Hi Niels,

I just tested your PR but it seems to fail with the following error

[Mon Feb 10 10:48:17.866993 2025] [php:error] [pid 597:tid 597] [client 127.0.0.1:53296] PHP Fatal error: Uncaught Error: Class "IntlDateFormatter" not found in /srv/http/saldi/includes/finansfunk.php:25\nStack trace:\n#0 /srv/http/saldi/finans/regnskab.php(340): periodeoverskrifter()\n#1 {main}\n thrown in /srv/http/saldi/includes/finansfunk.php on line 25, referer: http://localhost:8080/saldi/index/main.php

[nielsrune]

As mentioned, make sure Intl is installed and enabled. It comes bundled with PHP but may be disabled by default.