Expo Random

GitHub

npm

A universal library for generating random bytes.

Deprecated: This module will no longer be available in SDK 49. Use expo-crypto instead.

expo-random provides a native interface for creating strong random bytes. With Random you can create values equivalent to Node.js core crypto.randomBytes API. expo-random also works with expo-standard-web-crypto, which implements the W3C Crypto API for generating random bytes.

Platform Compatibility

Android Device	Android Emulator	iOS Device	iOS Simulator	Web

Installation

Terminal

- npx expo install expo-random

If you are installing this in an existing React Native app (bare workflow), start by installing expo in your project. Then, follow the additional instructions as mentioned by library's README under "Installation in bare React Native projects" section.

API

import * as Random from 'expo-random';

Methods

`Random.getRandomBytes(byteCount)`

Name	Type	Description
byteCount	`number`	A number within the range from `0` to `1024`. Anything else will throw a `TypeError`.

Generates completely random bytes using native implementations. The byteCount property is a number indicating the number of bytes to generate in the form of a Uint8Array. Falls back to Math.random during development to prevent issues with React Native Debugger.

Returns:

Uint8Array

An array of random bytes with the same length as the byteCount.

`Random.getRandomBytesAsync(byteCount)`

Name	Type	Description
byteCount	`number`	A number within the range from `0` to `1024`. Anything else will throw a `TypeError`.

Generates completely random bytes using native implementations. The byteCount property is a number indicating the number of bytes to generate in the form of a Uint8Array.

Returns:

Promise<Uint8Array>

A promise that fulfills with an array of random bytes with the same length as the byteCount.