# useDateFormat
URL: /docs/web/hooks/use-date-format

Provider-agnostic date / datetime / time formatting context for Docyrus UI components. Wired automatically by DocyrusTenantProvider, but works with any date library.

## Installation

```bash
pnpm dlx @docyrus/cli add @docyrus/hooks-use-date-format
```

The module exports `useDateFormat()` (hook) and `
  );
}
```

The same pattern works with `dayjs`, `next-intl`, or any other library.

## API Reference

### `useDateFormat()`

Returns `DateFormatContextValue`.

| Field | Type | Description |
|-------|------|-------------|
| `formatDate` | `(value: unknown) => string` | Date-only output. |
| `formatDateTime` | `(value: unknown) => string` | Date + time output. |
| `formatTime` | `(value: unknown) => string` | Time-only output. |

### `<DateFormatProvider>`

| Prop | Type | Description |
|------|------|-------------|
| `formatDate` | `DateFormatFn` | Required. Backs `formatDate` inside the tree. |
| `formatDateTime` | `DateFormatFn` | Required. Backs `formatDateTime` inside the tree. |
| `formatTime` | `DateFormatFn` | Required. Backs `formatTime` inside the tree. |
| `children` | `ReactNode` | Tree to wrap. |

### `isDefaultDateFormatContext(ctx)`

Returns `true` when the value returned by `useDateFormat()` is the built-in no-provider sentinel (raw string renderer) rather than a real provider. Internal hooks use this to avoid shadowing a cell's own fallback when no provider is mounted. Most apps don't need to call it directly.

## Type Exports

| Type | Description |
|------|-------------|
| `DateFormatFn` | Signature of each formatter function (`(value: unknown) => string`). |
| `DateFormatContextValue` | Shape returned by `useDateFormat()`. |