Magento - How to validate my radio button? - magento

Question

in my custom module, I have a form which has radio buttons.
When I click the submit button it does not validate the radio button.
<?php
$question = Mage::getModel('emme_question/question')->getCollection()->getLastItem();
$answers = $question->getSelectedAnswersCollection();
?>
<h4><?php echo $this->escapeHtml($question->getValue()); ?></h4>
<ul>
<?php foreach ($answers as $answer): ?>
<li>
<label><?php echo $this->escapeHtml($answer->getValue()) ?></label>
<input class="required required-field" type="radio" name="my_custom_answer" value="<?php echo $answer->getId() ?>" required>
</li>
<?php endforeach ?>
and
<?php
// app/code/local/Envato/Custompaymentmethod/Model/Paymentmethod.php
class Envato_Custompaymentmethod_Model_Paymentmethod extends Mage_Payment_Model_Method_Abstract {
protected $_code = 'custompaymentmethod';
public function validateRadioIsSelected()
{
$var options = $$('input.Classname');
for( i in options ) {
if( options[i].checked == true ) {
return true;
}
}
return false;
}
public function getOrderPlaceRedirectUrl()
{
return Mage::getUrl('custompaymentmethod/payment/redirect', array('_secure' => false));
}
}
Parse error: syntax error, unexpected 'options' (T_STRING) in /home/mmstore9/public_html/demo/app/code/local/Envato/Custompaymentmethod/Model/Paymentmethod.php on line 27

Answer 1

use this magetno default validation class to validate the radio button
validate-one-required-by-name
OR
validate-one-required

Answer 2

I solved
public function validate()
{
foreach (Mage::getModel('emme_question/question')->load(1)->getSelectedAnswersCollection() as $answer)
{
if ($answer->getIsCorrect())
{
if ($answer->getId() == $_POST['my_custom_answer'])
{
Mage::getSingleton('core/session')->addSuccess('Risposta esatta');
} else
{
Mage::throwException('Risposta sbagliata!');
}
}
}
}