How to sort array under date as mY?

Question

PHP

There are such arrays:

array(29) {
  ["03.2020"]=>
  array(4) {
    ["likes"]=>
    int(46003)
    ["comments"]=>
    int(2663)
    ["reposts"]=>
    int(2939)
    ["views"]=>
    int(3386015)
  }
  ["01.2020"]=>
  array(4) {
    ["likes"]=>
    int(8958)
    ["comments"]=>
    int(612)
    ["reposts"]=>
    int(404)
    ["views"]=>
    int(699785)
  }
  ["02.2020"]=>
  array(4) {
    ["likes"]=>
    int(63776)
    ["comments"]=>
    int(3298)
    ["reposts"]=>
    int(3218)
    ["views"]=>
    int(4411204)
  }
  ["01.2019"]=>
  array(4) {
    ["likes"]=>
    int(33402)
    ["comments"]=>
    int(2037)
    ["reposts"]=>
    int(1096)
    ["views"]=>
    int(1236658)
  }
  ["12.2019"]=>
  array(4) {
    ["likes"]=>
    int(47592)
    ["comments"]=>
    int(1846)
    ["reposts"]=>
    int(832)
    ["views"]=>
    int(1552732)
  }
}

Their key in the form is formed like this date('mY').
There may be identical years but different months and vice versa.
It is possible to sort them, first by year, then by month.
To be something like this:
01.2010
02.2010
01.2015
03.2015

Answer 1

array_uksort() - Sorts an array by keys, using a custom key comparison function.
Write a function that determines the relationship between two dates in your format (less than, equal to, greater than) and use it in array_uksort.

Answer 2

Buddy, even you are too smart with the code, hold on, it's better this way:

$array = [
  '03.2001' => [],
  '01.2000' => [],
  '01.2005' => [],
  '05.2020' => [],
  '01.2020' => [],
  '30.1998' => [],
  '03.2020' => [],
  '09.2020' => [],
  '04.1998' => [],
  '11.2005' => [],
];

uksort($array, function(string $a, string $b): int {
  return date_create_from_format('m.Y', $a) <=> date_create_from_format('m.Y', $b);
});