# TextCase

Changes the case of selected text. checkChangeable can reject protected or business-locked ranges.

Changes the case of selected text. checkChangeable can reject protected or business-locked ranges.

`@quirekit/extensions` · **MIT**

## Editor compatibility
Layer：**Shared document capability**
| Editor | Status | Assembly and boundaries |
| --- | --- | --- |
| Classic | Supported | [classicEditorPreset](/en/plugins/reference/classic-editor-preset) — Use the product-neutral classicEditorPreset without duplicating installed capabilities. The Word preset replaces paragraphs, headings and container lists; do not stack generic structures onto that model. |
| Block | Requires integration | Connect the services, targets and lifecycle described on this page and validate the selected View and document model. Core contracts are reusable, but there is no universal product installation without host ports. |

“Supported” means the product assembly above exists; interaction, host services and file formats retain their own conditions. See [status and integration rules](/en/plugins/compatibility). Licensing is shown separately.

## Installation

```sh
pnpm add @quirekit/extensions@alpha
```

Install in Editor extensions. The host supplies a view, container and persistence; see [Quick start](/en/guide/quick-start).

```ts
import { TextCase } from '@quirekit/extensions'
```

Use compatible versions available from your distribution source. This site uses the Alpha workspace. License labels come from package metadata; see [support and licensing](/en/support).

## Integration by editor

These snippets use an existing host element named element. The host owns container sizing and persistence; call instance.destroy() on teardown. Avoid duplicating preset capabilities and supply required host ports before installation.

### Classic

Use the product-neutral classicEditorPreset without duplicating installed capabilities. The Word preset replaces paragraphs, headings and container lists; do not stack generic structures onto that model.

[classicEditorPreset](/en/plugins/reference/classic-editor-preset)

```ts
import { createClassicEditor } from '@quirekit/classic-editor'
import '@quirekit/classic-editor/styles.css'

const instance = createClassicEditor({ element })
```

### Block

Connect the services, targets and lifecycle described on this page and validate the selected View and document model. Core contracts are reusable, but there is no universal product installation without host ports.

## Configuration

These are extension-level defaults. Presets can override them; they are distinct from current document attributes. See [configuration](/en/plugins/configuration).

### checkChangeable

Host rule for text that must keep its characters, such as field results.

Type：`TextCaseChangeableCheck | null`

Default：`null`

## Commands and runtime

These commands are supplied directly by this extension. Availability depends on the installed schema, selection and protection policy; query editor.can() first.

| Command | Parameter signature |
| --- | --- |
| `changeTextCase` | `changeTextCase(mode: TextCaseMode)` |
| `cycleTextCase` | `cycleTextCase()` |

These are parameter signatures. See [commands and controls](/en/build/commands) to connect UI while retaining one transaction/history authority.

## Next steps

Return to [all plugins](/en/plugins), or read [configuration](/en/plugins/configuration) to distinguish options, attributes and commands.

See [extension development](/en/build/extension) for custom capabilities and [Build a product](/en/build) for complete hosting.