Auto mapping method parameters to $_POST data (MVC)

Question

Imagine I have a URL that loads a controller if the name matches (Ignoring any security issues with this at the moment hehe)

    public function Load( $controller, $action = "Index" )
    {                                             
        require_once( "Controllers/" . $controller . "Controller.php" );
        $controllerName = $controller . "Controller";  
        $loadedController = new $controllerName();
        $actionName = "ActionResult_" . $action;
        $loadedController->$actionName();
    }

Now imagine I want a log in form to send its $_POST details as parameters of the receiving controller launched above:

<?php
    class ExcelUploadController extends Controller
    {
        public function ActionResult_Login( $username = NULL, $password = NULL )
        {
            // The parameters need to be mapped to the $_POST parameters names probably from the Load method somewhere and pumped in to the $loadedController->$actionName();
            $post_username = $username;
            $post_password = $password;
            $this->ReturnView( "ExcelUpload/Index" );   
        }
    }
?>

But also so that it does not matter what order the parameters are declared, it matches the parameter in the function based on the $_POST key.

How might I go about doing this, any ideas?

So to clarify if this doesn't make sense.. the method might look something like this:

    public function Load( $controller, $action = "Index" )
    {                                             
        require_once( "Controllers/" . $controller . "Controller.php" );
        $controllerName = $controller . "Controller";  
        $loadedController = new $controllerName();

        $actionName = "ActionResult_" . $action;

        $checkIfPostData = $_POST;
        if( isset( $checkIfPostData ) )
        {
            // Do some funky wang to map the following $loadedController->$actionName();
            // with the username and password or any other $_POST keys so that in the calling method, I can grab hold of the $_POST values

        }

        $loadedController->$actionName();
    }

Answer 1

What your are looking for is call_user_func_array()

EDIT, to reply to comment : You have two options: rewrite all your function so that they accept only one array() as argument and you parse that array for values. A bit fastidious but it can be useful in some cases. Or you can request for the required argument of a function:

// This will create an object that is the definition of your object
$f = new ReflectionMethod($instance_of_object, $method_name);
$args = array();
// Loop trough params
foreach ($f->getParameters() as $param) {
    // Check if parameters is sent through POST and if it is optional or not
    if (!isset($_POST[$param->name]) && !$param->isOptional()) {
        throw new Exception("You did not provide a value for all parameters");
    }
    if (isset($_POST[$param->name])) {
        $args[] = $_POST[$param->name];
    }
    if ($param->name == 'args') {
        $args[] = $_POST;
    }
}
$result = call_user_func_array(array($instance_of_object, $method_name), $args);

That way your array will be properly constructed. You can also add some specific treatment whether a parameter is optional or not (I guess you can understand how to do it from the code I gave you ;)