Question

All about a Zend Application with an action helper.

I want to unset some pairs of an array by a function.

helper:

class Application_Controller_Action_Helper_TestHelper extends Zend_Contr[...]
{    
    public function direct(&$array)
    {
        if(isset($array['key']))
            unset($array['key']);
    }
}

controller:

$this->_helper->TestHelper($var);

How could I get it working?

Answer 1

You must also pass it as reference:
$this->_helper->TestHelper(&$var);

UPDATE:
Ups, I had my errors turned off. You (and now me) are getting the error because…

There is no reference sign on a function call – only on function
definitions. Function definitions alone are enough to correctly pass
the argument by reference. As of PHP 5.3.0, you will get a warning
saying that “call-time pass-by-reference” is deprecated when you use &
in foo(&$a);.

ZF’s HelperBroker uses return call_user_func_array(array($helper, 'direct'), $args); to call your direct() method. Check the docs, but it seems call_user_func_array passes by reference, although with several quirks.

Check out this answer.