How to validate all form field
if (!Zend_Validate::is($this->getRequest()->getPost('product[name]'), 'NotEmpty')) {
$error = true;
Mage::getSingleton('core/session')->addError(Mage::helper('example')->__('Please enter product name'));
}
if (!Zend_Validate::is($this->getRequest()->getPost('product[description]'), 'EmailAddress')) {
$error = true;
Mage::getSingleton('core/session')->addError(Mage::helper('example')->__('Please enter Email'));
}
Using this code i am validate NotEmpty and EmailAddress but also i want to validate only number any other form validation so which class is use for all that