(PHP 4 >= 4.2.0)

array_change_key_case -- Returns an array with all string keys lowercased or uppercased


array array_change_key_case ( array input [, int case])

array_change_key_case() changes the keys in the input array to be all lowercase or uppercase. The change depends on the last optional case parameter. You can pass two constants there, CASE_UPPER and CASE_LOWER. The default is CASE_LOWER. The function will leave number indices as is.

Example 1. array_change_key_case() example

$input_array = array("FirSt" => 1, "SecOnd" => 4);
print_r(array_change_key_case($input_array, CASE_UPPER));

The printout of the above program will be:
    [FIRST] => 1
    [SECOND] => 2