Random\Randomizer::pickArrayKeys
(PHP 8 >= 8.2.0)
Random\Randomizer::pickArrayKeys — Select random array keys
Descrizione
Uniformly selects num distinct array keys of the input array.
Each key of the input array is equally likely to be returned.
The selection of the array keys depends on the internal structure of the input
array. The returned array keys might be different for
two equal input arrays and two Random\Engines with
identical state, depending on how the input arrays have been created.
Elenco dei parametri
-
array -
The array whose array keys are selected.
-
num -
The number of array keys to return; must be between
1and the number of elements inarray.
Valori restituiti
An array containing num distinct array keys of array.
The returned array will be a list (array_is_list()). It will be a subset of the array returned by array_keys().
Errori/Eccezioni
-
If
numis less than1or greater than the number of elements inarray, a ValueError will be thrown. -
Any Throwables thrown by the Random\Engine::generate() method
of the underlying
Random\Randomizer::$engine.
Esempi
Example #1 Random\Randomizer::pickArrayKeys() example
<?php
$r = new \Random\Randomizer();
$fruits = [ 'red' => '🍎', 'green' => '🥝', 'yellow' => '🍌', 'pink' => '🍑', 'purple' => '🍇' ];
// Pick 2 random array keys:
echo "Keys: ", implode(', ', $r->pickArrayKeys($fruits, 2)), "\n";
// Pick another 3:
echo "Keys: ", implode(', ', $r->pickArrayKeys($fruits, 3)), "\n";
?>Il precedente esempio visualizzerà qualcosa simile a:
Keys: yellow, purple Keys: red, green, yellow
Example #2 Picking random values
<?php
$r = new \Random\Randomizer();
$fruits = [ 'red' => '🍎', 'green' => '🥝', 'yellow' => '🍌', 'pink' => '🍑', 'purple' => '🍇' ];
$keys = $r->pickArrayKeys($fruits, 2);
// Look up the values for the picked keys.
$selection = array_map(
static fn ($key) => $fruits[$key],
$keys
);
echo "Values: ", implode(', ', $selection), "\n";
?>Il precedente esempio visualizzerà qualcosa simile a:
Values: 🍎, 🍇
Vedere anche:
- array_keys() - Restituisce tutte le chiavi di un array
add a note
