Generate SHA256 Encoded Hash in React Native

SHA256 Encoding

Here is How to Generate SHA256 Encoded Hash from any Input Value in React Native. We will use the sha256 component from react-native-sha256 to convert our Input Text into SHA256 Hash.
SHA256 encoding comes into the scene when you talk about the security. Security can be of anything like it can be of your passwords, session keys or any other data.

SHA-256 stands for Secure Hash Algorithm – 256 bit and is a type of hash function commonly used in Blockchain. A hash function is a type of mathematical function which turns data into a fingerprint of that data called a hash. It’s like a formula or algorithm which takes the input data and turns it into an output of a fixed length, which represents the fingerprint of the data.

How to Generate SHA256 Encoded Hash?

sha256(this.state.text).then(hash => {
    console.log(hash)
});

To Make a React Native App

Getting started with React Native will help you to know more about the way you can make a React Native project. We are going to use react-native init to make our React Native App. Assuming that you have node installed, you can use npm to install the react-native-cli command line utility. Open the terminal and go to the workspace and run

npm install -g react-native-cli

Run the following commands to create a new React Native project

react-native init ProjectName

If you want to start a new project with a specific React Native version, you can use the --version argument:

react-native init ProjectName --version X.XX.X

react-native init ProjectName --version react-native@next

This will make a project structure with an index file named App.js in your project directory.

Installation of Dependency

To use sha256 we have to install react-native-sha256 dependency.
To install this open the terminal and jump into your project using

cd ProjectName

Run the following command

npm install react-native-sha256 --save

This command will copy all the dependencies into your node_module directory. –save is optional, it is just to update the react-native-sha256 dependency in your package.json file.

CocoaPods Installation

After the updation of React Native 0.60, they have introduced autolinking so we do not require to link the library but need to install pods. So to install pods use

cd ios && pod install && cd ..

Code to Generate SHA256 Encoded Hash

Now Open App.js in any code editor and replace the code with the following code

App.js

/*This is an Example to Generate SHA256 Encoded Hash in React Native*/
import React from 'react';
//import React in our project
import {
  Text,
  View,
  StyleSheet,
  TextInput,
  TouchableOpacity,
} from 'react-native';
//import all the components we needed
import { sha256 } from 'react-native-sha256';
//import sha256 to use sha256()
export default class App extends React.Component {
  constructor(props) {
    super(props);
    //initial value of Text
    this.state = {
      inputText: '',
      text: '',
    };
  }
  convertSHA(){
    //Encode SHA256 
    sha256(this.state.text).then(hash => {
      this.setState({ text:hash })
    });
  }
  render() {
    return (
      <View style={styles.container}>
        <Text style={styles.textStyle}>{this.state.text}</Text>
        <Text>'Please insert any value to convert in SHA 256'</Text>
        <TextInput
          style={styles.inputStyle}
          onChangeText={inputText => this.setState({ inputText })}
          placeholder="Enter Any Value"
          value={this.state.inputText}
        />
        <TouchableOpacity
          style={styles.button}
          title="Conver sh5"
          onPress={this.convertSHA.bind(this)}>
          <Text>Conver to SHA 256</Text>
        </TouchableOpacity>
      </View>
    );
  }
}
const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    paddingTop: 20,
    backgroundColor: 'white',
  },
  textStyle: {
    padding: 10,
    textAlign: 'center',
    marginBottom: 30
  },
  inputStyle: {
    height: 40,
    width: 300,
    marginTop: 16,
    textAlign: 'center',
    borderColor: 'gray',
    backgroundColor: '#ecf0f1',
    borderWidth: 1,
  },
  button: {
    alignItems: 'center',
    backgroundColor: '#DDDDDD',
    padding: 10,
    width: 300,
    marginTop: 16,
  },
});

To Run the React Native App

Open the terminal again and jump into your project using.

cd ProjectName

To run the project on an Android Virtual Device or on real debugging device

react-native run-android

or on the iOS Simulator by running

react-native run-ios (macOS only).

Output Screenshots

Android

      

IOS

      

This is how you can Generate SHA256 Encoded Hash in React Native. If you have any doubts or you want to share something about the topic you can comment below or contact us here. There will be more posts coming soon. Stay tuned!

Hope you liked it. 🙂