Syntax:array array_change_key_case ( array $input [, int $case = CASE_LOWER ] ) Description: Changes all keys in an array<?php $input_array = array("FirSt" => 1, "SecOnd" => 'Hai'); print_r( array_change_key_case ( $input_array, CASE_UPPER ) ); ?> OUTPUT<?php Array ( [FIRST] => 1 [SECOND] => Hai ) ?>... Read More »