For developers, this shipping validator will trigger the checkout module to load (ajax) the shipping method details when users entering information. This is an essential part of the bigger task of adding a custom shipping method to your Magento store.
Magento uses Regular Expression (re) to check whether the entered zipcode/postcode is correct. In this article, we will add our own expression to validate the zipcode.
This topic describes how to add a new input form to the Checkout page. Magento provides the ability to add a custom form to any of the checkout steps: Shipping Information, Review and Payment Information, or custom. In this article, we will add the new form before Shipping Address form.
This article will help you add your own validation before placing an order. This is the step where you add a new field and want to verify that field.