How to create validation rules in the checkout to avoid certain characters

Sometimes, a payment gateway might refuse some characters (e.g. ô or ø), which can lead to failed payments. To circumvent that, you can create allowed character sets for specific countries. You can also set the error message to be displayed if a user inputs an unauthorised character.

Note that you will need to be familiar with Regular Expression Charset to configure this feature.

Setup

To set it up, go to Settings > Shop and scroll to Address Country Specific Rules. (This is planned to be moved to Settings > Localisation). Then:

• Select the country where the character set is applicable. The country used for validation is the Billing Country, as this is the country that is generally used by payment gateways.
• Enter the character set validation. Limio uses Regular Expression Charset (Regex charset). See an example below.
• Input the error message you want to display to the customer.

To test you Regex Charset, you can go to https://regexr.com/. If you need some context about Regex Charset, this is a good resource https://www.regular-expressions.info/charclass.html. If you have issues with your Regex Character, please raise a ticket via the help desk.

Let's take an example

Say that in Taiwan, you only want to use letters from a-z, A-Z, latin accents, as well as 0-9 and dashes. The regex for that would be:

-a-zA-ZÀ-ÿ-0-9_

You can then input an error message. See an example below:

This is how the customer will see those error message on the checkout: