A case-insensitive associative array.

This class represents an associative array in which the keys are considered to be case insensitive. This means that $array['key'] and $array['KEY'] will refer to the same array element.

$array = new CaseInsensitiveArray();

$array['key'] = 'value';
echo $array['KEY']; // 'value'

$array['kEy'] = 'foobar';
var_dump($array->toArray()); // array('key' => 'foobar')

Note that it is not possible to reuse case variants of a key. That is, if the array contains key xyz then it is not possible to use any of the following case variants as an array key: xyZ, xYz, xYZ, Xyz, XyZ, XYz, XYZ. In order to use a case variant as a key, it is necessary to first unset the original case variant.

$array = new CaseInsensitiveArray(array('key' => 'foo', 'KEY' => 'bar'));
var_dump($array->toArray()); // array('key' => 'bar')

$array['KEY'] = 'baz';
var_dump($array->toArray()); // array('key' => 'baz')

unset($array['key']);
$array['KEY'] = 'baz';
var_dump($array->toArray()); // array('KEY' => 'baz')