Validation rules

Configure enrolment form validation rules for required, format, and matching checks.

Validation rules protect data quality at the point of capture. They prevent incomplete or incorrectly formatted values from entering customer profiles and downstream systems.

Choose rules based on the purpose of each field. Strict validation is useful for identifiers. Optional enrichment fields should remain easy to complete.

Real-world examples

• A loyalty programme requires an email address and verifies its format before enrolment.

• A ticketing form limits a booking reference to the expected character length.

• A membership form compares the confirmation email against the original email field.

How validation works

Validation is configured at the individual field level. Each rule checks whether a value meets the data requirements before the form is submitted.

Use a small number of rules that match the field’s purpose. Overly restrictive forms can increase abandonment and create support work.

Available validation rules

Required

• Indicates whether the field must be filled out.

• For checkboxes and switchboxes, this means the box must be checked.

minLength

• Defines the minimum number of characters required for a field's value.

• Useful for fields like names or identification numbers.

maxLength

• Sets the maximum number of characters allowed in the field.

• Helps prevent excessively long inputs that could disrupt layout or storage.

email

• Combines two layers of validation:

  1. Regular Expression Check: Uses the following default regex to validate format:

     /^[a-zA-Z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-zA-Z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-zA-Z0-9](?:[a-zA-Z0-9-]*[a-zA-Z0-9])?\.)+[a-zA-Z0-9](?:[a-zA-Z0-9-]*[a-zA-Z0-9])?$/

     This regex can be overridden with a custom one if needed.

  2. Domain Check via DNS: The Wallet Crew verifies that the email domain accepts mail by checking for MX records.

phone

• Validates phone numbers using the react-phone-number-input component.

• This is based on Google’s international phone number validation library.

• Ensures numbers are correctly formatted and country codes are recognized.

expression

• Allows administrators to define a custom regular expression to validate the field.

• Flexible option for enforcing format-specific data (e.g., postal codes, IDs).

equality

• Compares the field’s value to:

  • Another field’s value (e.g., "Confirm Password")

  • A static constant value

• Ensures consistency and matching where required.

Configure rules effectively

Start with the minimum needed to identify a customer and issue a pass. Add more rules only when they improve an operational or compliance outcome.

• Use required only for information needed during enrolment.

• Use email and phone for customer contact identifiers.

• Use equality for confirmation fields, such as repeated email addresses.

• Test custom regular expressions with expected and invalid values before publishing.

Customize the default email expression only when there is a documented requirement. An overly narrow expression can reject valid customer email addresses.

Validate the form before publishing

Submit the form with representative valid and invalid values. Confirm that required fields block empty submissions, format rules show clear errors, and equality fields reject mismatched values.

Review the result on mobile as well as desktop. Most enrolment journeys begin on a phone after a QR-code scan or campaign link.

FAQ

Which fields should be required?

Require only fields needed to identify the customer, issue the pass, or meet a documented compliance requirement. Optional fields can be collected later.

When should an expression rule be used?

Use an expression rule when a business identifier requires a specific format that the standard rules do not cover. Test the expression against valid and invalid sample values before publishing.

Can an email address be confirmed?

Yes. Add a second email field and apply the equality rule to compare it with the original field.

Why does a valid-looking email address fail validation?

The email rule checks both the address format and whether the domain accepts mail through MX records. Confirm that the domain is spelled correctly and has valid mail records.