public function arrayChangeCaseKey($array)
    {
        return array_map(function ($item) {
            if (is_array($item)) {
                $item = $this->arrayChangeCaseKey($item);
            }

            return $item;
        }, array_change_key_case($array));
    }
public function arrayChangeCaseKey($array)
    {
        return array_map(function ($item) {
            if (is_array($item)) {
                $item = $this->arrayChangeCaseKey($item);
            }

            return $item;
        }, array_change_key_case($array));
    }
public function arrayChangeCaseKey ( $ array ) { return array_map ( function ( $ item ) { if ( is_array ( $ item ) ) { $ item = $ this -> arrayChangeCaseKey ( $ item ) ; } return $ item ; } , array_change_key_case ( $ array ) ) ; }
Change the key of array to lower case.

@param (array) $array valid array

@since 3.0.0

@author => http://php.net/manual/en/function.array-change-key-case.php#114914

@return array
Change the key of array to lower case .