I want a quick easy way to copy an array but the ability to specify which keys in the array I want to copy.
I can easily write a function for this, but I'm wondering if there's a PHP function that does this already. Something like the array_from_keys() function below.
$sizes = array('small' => '10px', 'medium' => '12px', 'large' => '13px');
$chosen = array_from_keys($sizes, 'small', 'large');
// $chosen = array('small' => '10px', 'large' => '13px');
There's a native function in PHP that allows such manipulations, i.e. array_intersect_key, however you will have to modify your syntax a little bit.
<?php
$sizes = array('small' => '10px', 'medium' => '12px', 'large' => '13px');
$selected = array_fill_keys(array('small', 'large'), null);
$result = array_intersect_key($sizes, $selected);
?>
$result will contain:
Array (
[small] => 10px
[large] => 13px
);
There isn't a function for this as far as I know. The easiest way would be to do something like this I think:
$chosen = array_intersect_key($sizes, array_flip(array('small', 'large')));
Or as you say you can easily write a function:
function array_from_keys() {
$params = func_get_args();
$array = array_shift($params);
return array_intersect_key($array, array_flip($params));
}
$chosen = array_from_keys($sizes, 'small', 'large');
Simple approach:
$sizes = array('small' => '10px', 'medium' => '12px', 'large' => '13px');
$chosen = array("small", "large");
$new = array();
foreach ($chosen as $key)
$new[$key] = $sizes[$key];
