Overview
The Validation section allows you to attach custom server-side validators to a form. These validators run when a user attempts to save a form instance, and can block the save if the data does not meet defined criteria.
Validators must be defined in Admin > Custom Logic > Validation before they can be selected here. The Validation section references existing validators by name — it does not create them.
Available Validation Hooks
|
Hook |
When It Runs |
Common Use Cases |
|---|---|---|
|
Before Save — Test Validation |
Runs before a form instance is saved. If the validator returns a failure, the save is blocked and an error message is shown to the user. |
Enforcing business rules (e.g., start date must be before end date), cross-field validation, checking that a selected record meets certain criteria, requiring at least one row in an Input Table |
Configuring a Validator
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Expand the Validation section in the Edit Form sidebar.
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Type in the search field or click the search icon to find an existing validator.
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Select the validator to attach it to the form.
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Save the form to apply the change.
To remove a validator, clear the field.
Defining Validators
Custom validators are PHP-based handlers defined in Admin > Custom Logic > Validation. Validators have access to the form instance data being saved and can return pass/fail with an optional user-facing error message. Refer to the Custom Logic documentation for details on writing validators.
A validator that always fails will prevent users from saving any submissions for that form. Test validators thoroughly in a development environment before attaching them to production forms.