angular-forms

Create a writable signal holding your form model, then pass it to the form() function from @angular/forms/signals with an optional validation schema. Bind inputs in the template using the [formField] directive for automatic two-way binding.

Pass a schema callback to form() and apply validators like required, email, min, maxLength, or pattern to schema paths. Use validate() for custom logic, validateHttp() for async server checks, and the when option for conditional validation.

Signal Forms are experimental in Angular v21 and recommended for new projects wanting less boilerplate and signal-based reactivity. Reactive Forms remain the production-stable choice for apps requiring stability guarantees, typed FormGroups, and FormArray support.

Yes, implement the FormValueControl interface with a value model signal and optional inputs like readonly, invalid, and errors. The custom component then works directly with the [formField] directive like native inputs.

Model the array in your signal, iterate fields in the template with @for, and use applyEach in the schema to validate each item. Add or remove entries by updating the model signal with standard immutable array operations.

Signal Forms are experimental in Angular v21, so the API may change between releases and lacks the maturity of Reactive Forms. For production apps requiring stability, the references include equivalent Reactive Forms patterns as a fallback.