(PHP 5 >= 5.2.0, PHP 7, PHP 8)
ArrayIterator::ksort — Sort entries by keys
$flags = SORT_REGULAR): boolSorts entries by their keys.
Note:
If two members compare as equal, they retain their original order. Prior to PHP 8.0.0, their relative order in the sorted array was undefined.
flags
The optional second parameter flags
may be used to modify the sorting behavior using these values:
Sorting type flags:
SORT_REGULAR - compare items normally;
the details are described in the comparison operators section
SORT_NUMERIC - compare items numerically
SORT_STRING - compare items as strings
SORT_LOCALE_STRING - compare items as
strings, based on the current locale. It uses the locale,
which can be changed using setlocale()
SORT_NATURAL - compare items as strings
using "natural ordering" like natsort()
SORT_FLAG_CASE - can be combined
(bitwise OR) with
SORT_STRING or
SORT_NATURAL to sort strings case-insensitively
Always returns true.