# Viewer.CancellationToken

## Content

# Class: CancellationToken

[Viewer](../modules/Viewer).CancellationToken

## Table of contents

### Constructors

- [constructor](Viewer.CancellationToken#constructor)

### Properties

- [isCancellationRequested](Viewer.CancellationToken#iscancellationrequested)
- [parentToken](Viewer.CancellationToken#parenttoken)
- [promise](Viewer.CancellationToken#promise)

### Methods

- [register](Viewer.CancellationToken#register)
- [create](Viewer.CancellationToken#create)

## Constructors

### constructor

• **new CancellationToken**()

## Properties

### isCancellationRequested

• `Readonly` **isCancellationRequested**: `boolean`

Gets true if cancellation is being requested.

#### Defined in

node_modules/@grapecity/ar-js-viewer/dist/ar-js-viewer.d.ts:785

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### parentToken

• `Optional` `Readonly` **parentToken**: [`CancellationToken`](Viewer.CancellationToken)

The parent token

#### Defined in

node_modules/@grapecity/ar-js-viewer/dist/ar-js-viewer.d.ts:773

___

### promise

• `Readonly` **promise**: `Promise`<`any`\>

Gets a promise that is triggered when cancellation is requested.

#### Defined in

node_modules/@grapecity/ar-js-viewer/dist/ar-js-viewer.d.ts:789

## Methods

### register

▸ **register**(`callback`): `void`

Registers a new cancellation handler. Handler is invoked when cancellation is requested.

#### Parameters

| Name | Type |
| :------ | :------ |
| `callback` | (`reason`: `any`) => `any` |

#### Returns

`void`

#### Defined in

node_modules/@grapecity/ar-js-viewer/dist/ar-js-viewer.d.ts:794

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### create

▸ `Static` **create**(`parentToken?`): `Object`

Creates a cancellation token and trigger function.

#### Parameters

| Name | Type | Description |
| :------ | :------ | :------ |
| `parentToken?` | [`CancellationToken`](Viewer.CancellationToken) | The parent token. |

#### Returns

`Object`

| Name | Type |
| :------ | :------ |
| `token` | [`CancellationToken`](Viewer.CancellationToken) |
| `cancel` | (`e`: `any`) => `void` |

#### Defined in

node_modules/@grapecity/ar-js-viewer/dist/ar-js-viewer.d.ts:778