根据另一个数组过滤$ _REQUEST数组？

Question

Array $ALLOWED_CALLS contains a function name and required parameters. I'd like to filter $_REQUEST array obtaining a $params array with only required paramets in it. How to?

$call = 'translate';

$ALLOWED_CALLS = array(
    'getLanguages' => array(),
    'detect' => array('text'),
    'translateFrom' => array('text', 'from', 'to'),
    'translate' => array('text', 'to'),
);

$params = array(); // Should contain $_REQUEST['text'] and $_REQUEST['to']

Answer 1

I'd use array_intersect_key() like so:

$params = array_intersect_key($_REQUEST, array_flip($ALLOWED_CALLS[$call]));

Thus, the whole thing:

$call = 'translate';

$ALLOWED_CALLS = array(
    'getLanguages' => array(),
    'detect' => array('text'),
    'translateFrom' => array('text', 'from', 'to'),
    'translate' => array('text', 'to'),
);

$params = array_intersect_key($_REQUEST, array_flip($ALLOWED_CALLS[$call]));