Submit form values using controller and model in magento admin module

Question

I am building an admin module and need to process a form but am having troubles getting the variables to POST and am just redirected to the dashboard. The form looks like this :

<form name="notes" action="<?php echo Mage::helper("adminhtml")->getUrl("foo/index/processnotes/");?>"  method="post">
<input type="hidden" name="another_form_key" value="<? echo $this->getFormKey(); ?>" /> 

I am doing it that way because the secure keys are turned on for admin. It gives me a url like :

foo/index/processnotes/key/4745f5fbb9c168778958d5d4a4c2c0ef/

In the controller I have:

public function processnotesAction(){       
    $model = Mage::getModel('foo/process');
    // I am not sure how I am supposed to send $_POST values here
    }

and in Package/foo/Model/Process.php

I would hope to be able to process the POST variables from my form in here but I can not see what is wrong and I am just sent to dashboard.

<?php
class Package_foo_Model_Process extends Mage_Core_Model_Abstract
{
        public function noteProcess() {     
            $test = $_POST['myValue'];
            echo $test;
     }
}

Update

After reading the answers I wanted to add a bit more of what my real code is doing and how I am using $_POST. I was setting up a simple example to just get the form to post but realizing there are probably many things I am doing wrong in Magento.

  $query="INSERT INTO `notes_value` ( `color`, `the_id`, `the_value` ) VALUES ";
 $sku = $_POST['color'];
array_pop($_POST);
foreach ($_POST AS $key => $value) {
        $values[] = "('$sku', '$id', '$value')";
}   
$query .= implode(', ', $values) . ';';

The dream is I could $resource->getConnection('core_write'); to actually insert this into the database but feeling less optimistic with how it is going so far.

Answer 1

Usually when you are getting redirected to the dashboard because your key is not recognised. I normally would use the following syntax

        <input name="form_key" type="hidden" value="<?php echo Mage::getSingleton('core/session')->getFormKey() ?>" />

Also, I would be inclined to disable admin keys to verify whether that is your issue.

Next, never, ever use $_POST with Magento, all variables are accessible (cleanly and securely). POST information is accessible globally (not just in a controller), however you can still set variables in your model from the controller like this:

public function processnotesAction(){       
  $model = Mage::getSingleton('foo/process');
  $model->setData('postdata', $this->getRequest()->getPost() );
}

Then accessing them from your model with:

$this->getData();
$this->getMyPostedField();

Or you could just use this in your Model

Mage::app()->getRequest()->getPost();
Mage::app()->getRequest()->getParam('myargument');

getPost can also take a parameter to fetch a single POST value - but it does not get GET values. getParam will return both GET and POST values alike.