---
title: AutoCommandForm
---

`AutoCommandForm` generates its field list from the command's own properties instead of you writing one field per property by hand. Each property's type picks its field component through a registry - `string` gets `InputTextField`, `number` gets `NumberField`, `boolean` gets `CheckboxField`, `Date` gets `CalendarField` - the same components you would otherwise use directly.

## Usage

```tsx
import { CommandDialog } from '@cratis/components/CommandDialog';
import { AutoCommandForm } from '@cratis/components/CommandForm';

<CommandDialog command={RegisterProject} visible={visible} onCancel={() => setVisible(false)}>
    <AutoCommandForm command={RegisterProject} exclude={['projectId']} />
</CommandDialog>
```

A property whose type has no registered provider - a nested object, an array, an enum - is left out of the generated list. Add it as a hand-written `CommandForm` field alongside `AutoCommandForm`, or register a provider for it (see below).

## Props

| Prop | Type | Default | Description |
|------|------|---------|-------------|
| `command` | `Constructor<TCommand>` | — | **Required.** The command type to generate fields for. |
| `exclude` | `(keyof TCommand)[]` | — | Property names to leave out of the generated field list. |

`AutoCommandForm` also accepts every other `CommandForm` prop (`initialValues`, `populateFromQuery`, `onSuccess`, `validateOn`, and so on) except `children`, which it generates itself.

## Registering a field type provider

The built-in providers cover `string`, `number`, `boolean` and `Date`. Register your own for any other property type - a Cratis concept, an enum, a custom value object - with `registerFieldTypeProvider`:

```tsx
import { registerFieldTypeProvider } from '@cratis/components/CommandForm';
import { DropdownField } from '@cratis/components/CommandForm';
import { Status } from './Status';

registerFieldTypeProvider({
    canHandle: propertyDescriptor => propertyDescriptor.type === Status,
    component: DropdownField
});
```

Register once, at module load, before any `AutoCommandForm` renders. Providers are consulted most-recently-registered first, so registering a provider for a type the built-in defaults already cover - `string`, say - overrides that default.

## Behavior

- Field titles are generated from the property name by splitting on capitals and uppercasing the first letter (`dueDate` becomes "Due Date"); there is no way to override an individual generated field's title other than excluding it and writing that one field by hand.
- `required` is **not** derived from the property descriptor's `isOptional` — every generated field is rendered without it. Write the field by hand when you need `required` on it.
- Every generated field participates in `CommandForm`'s validation, change tracking and initial-value population exactly as a hand-written field does - `AutoCommandForm` only decides *which* fields to render, not how they behave once rendered.