(PHP 4 >= 4.2.0, PHP 5)
array_change_key_case — Changes all keys in an array
Returns an array with all keys from input lowercased or uppercased. Numbered indices are left as is.
The array to work on
Either CASE_UPPER or CASE_LOWER (default)
Returns an array with its keys lower or uppercased, or false if input is not an array.
Throws E_WARNING if input is not an array.
Example #1 array_change_key_case() example
<?php
$input_array = array("FirSt" => 1, "SecOnd" => 4);
print_r(array_change_key_case($input_array, CASE_UPPER));
?>
The above example will output:
Array
(
[FIRST] => 1
[SECOND] => 4
)
Note: If an array has indices that will be the same once run through this function (e.g. "keY" and "kEY"), the value that is later in the array will override other indices.