Cash on delivery payment method should visible only for some zip codes magento module

Question

How to make magento module for Cash on delivery payment method should visible only for some zip codes/pin codes and it can be check in product page also.

Answer 1

for view page : http://www.nextbits.eu/check-delivery-availability-magento-extension.html

for checkout page , All you need is to edit the file /app/code/local/Mage/Payment/Model/Method/Cashondelivery.php

public function getInstructions()
        {
            return trim($this->getConfigData('instructions'));
        }

        public function isAvailable($quote = null)
    {
        if ($quote) {

            // Here is the list of restricted Zip Codes
            $restrictedZips = array(
    '641004'
    ,'641006'


    );

            $address = $quote->isVirtual() ? $quote->getBillingAddress() : $quote->getShippingAddress();
            $customerZip = $address->getPostcode();

            if (!in_array($customerZip, $restrictedZips)) {
                return false;
            }
        }

        return parent::isAvailable($quote);
    }
    }