Cross Field Form Validation in Oracle JET

JET keeps evolving and in the latest versions  - toolkit provides improved support for form cross-field validation. It is much easier to implement validation than it was before. I will show it in this example.

Example of the data entry form. Validation logic:

- Invoice Date before Payment Due Date and Payment Date
- Payment Due Date before Payment Date

Example when two fields fail validation:

JET provides component called validation group. Form can be wrapped by this component to identify if any validation errors are reported there. For example, when calling JS function, before proceeding with the function code - we can check if validation group contains errors:

Input field can be assigned with custom validator function:

Example of validation function code where cross-field validation logic is implemented - we compare field value with other fields. If validation rule condition is false - validation error is thrown:

Example of function code, where validation group is checked for errors. If there are errors in the current validation group - errors are displayed and the first field with error is focused:

Download sample code from my GitHub repo.