Required
Introduction
Required is a common rule for form validation. You can enable it directly in the field configuration, or dynamically set a field as required through the form's linkage rules.
Where to set a field as required
Collection field settings
When a collection field is set to required, it triggers backend validation, and the frontend also displays it as required by default (cannot be modified).
Field settings
Directly set a field as required. This is suitable for fields that always need to be filled in by the user, such as username, password, etc.
Linkage rules
Set a field as required based on conditions through the form block's field linkage rules.
Example: The order number is required when the order date is not empty.
