In Construct Preview, BeforeDelete events run before records are deleted to enforce pre-delete validation and business rules when:
You delete a single record and confirm the delete action.
One or more rows are marked for delete and saving the grid.
If the event validation passes, the delete continues. If the event returns validation failures, the delete is blocked and you receive a notification with details.
Note
If a grid or properties card (form) container does not have a BeforeDelete event configured, the delete takes effect immediately.
How Warnings and Errors Are Handled
Single-record deletion in Form container: If the BeforeDelete event returns a warning, an Accept/Cancel dialog box is displayed. Choose Accept to retry the delete (warnings will be treated as non-errors for that retry) or Cancel to stop the delete.
Multiple-record deletion in Grid container: Warnings are treated as errors and the delete is blocked. Resolve the reported validation issues before retrying.
Note
If a delete is blocked, read the validation messages in the notification to understand the failing checks.
For form deletes, use Accept only after you have reviewed the validation message and are confident the delete is safe.
For grid deletes, address the reported validation failures on the affected rows and try again.