expo-crypto enables you to hash data in an equivalent manner to the Node.js core crypto API.| Android Device | Android Emulator | iOS Device | iOS Simulator | Web |
|---|---|---|---|---|
→ npx expo install expo-cryptoIf you're installing this in a bare React Native app, you should also follow these additional installation instructions.
import React, { useEffect } from 'react';
import { StyleSheet, View, Text } from 'react-native';
import * as Crypto from 'expo-crypto';
export default function App() {
useEffect(() => {
(async () => {
const digest = await Crypto.digestStringAsync(
Crypto.CryptoDigestAlgorithm.SHA256,
'GitHub stars are neat 🌟'
);
console.log('Digest: ', digest);
/* Some crypto operation... */
})();
}, []);
return (
<View style={styles.container}>
<Text>Crypto Module Example</Text>
</View>
);
}
%%placeholder-start%%const styles = StyleSheet.create({ ... }); %%placeholder-end%%const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: '#fff',
alignItems: 'center',
justifyContent: 'center',
},
});
import * as Crypto from 'expo-crypto';
Crypto.digestStringAsync(algorithm, data, options)| Name | Type | Description |
|---|---|---|
| algorithm | CryptoDigestAlgorithm | The cryptographic hash function to use to transform a block of data into a fixed-size output. |
| data | string | The value that will be used to generate a digest. |
| options (optional) | CryptoDigestOptions | Format of the digest string. Defaults to: |
The digestStringAsync() method of Crypto generates a digest of the supplied data string with the provided digest algorithm.
A digest is a short fixed-length value derived from some variable-length input. Cryptographic digests should exhibit collision-resistance,
meaning that it's very difficult to generate multiple inputs that have equal digest values.
You can specify the returned string format as one of CryptoEncoding. By default, the resolved value will be formatted as a HEX string.
On web, this method can only be called from a secure origin (https) otherwise an error will be thrown.
const digest = await Crypto.digestStringAsync( Crypto.CryptoDigestAlgorithm.SHA512, '🥓 Easy to Digest! 💙' );
Return a Promise which fulfills with a value representing the hashed input.
CryptoDigestOptions| Name | Type | Description |
|---|---|---|
| encoding | CryptoEncoding | Format the digest is returned in. |
DigestType: string
CryptoEncodingCryptoEncoding.BASE64 ＝ "base64"Has trailing padding. Does not wrap lines. Does not have a trailing newline.
CryptoEncoding.HEX ＝ "hex"| Code | Description |
|---|---|
ERR_CRYPTO_UNAVAILABLE | Web Only. Access to the WebCrypto API is restricted to secure origins (https). You can run your web project from a secure origin with expo start --https. |
ERR_CRYPTO_DIGEST | An invalid encoding type provided. |