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 command line interface to make our React Native App.

If you have previously installed a global react-native-cli package, please remove it as it may cause unexpected issues:

npm uninstall -g react-native-cli @react-native-community/cli

Run the following commands to create a new React Native project

npx react-native init ProjectName

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

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

Note If the above command is failing, you may have old version of react-native or react-native-cli installed globally on your pc. Try uninstalling the cli and run the cli using npx.

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

// Generate SHA256 Encoded Hash in React Native
// https://aboutreact.com/generate-sha256-encoded-hash-in-react-native/

// import React in our code
import React, {useState} from 'react';

// import all the components we are going to use
import {
  SafeAreaView,
  Text,
  View,
  StyleSheet,
  TextInput,
  TouchableOpacity,
} from 'react-native';

import {sha256} from 'react-native-sha256';

const App = () => {
  const [inputText, setInputText] = useState('');
  const [text, setText] = useState('');

  const convertSHA = () => {
    //Encode SHA256
    sha256(inputText).then((hash) => {
      setText(hash);
    });
  };

  return (
    <SafeAreaView style={{flex: 1}}>
      <View style={styles.container}>
        <Text style={styles.titleStyle}>
          Generate SHA256 Encoded Hash in React Native
        </Text>
        <Text style={styles.textStyle}>{text}</Text>
        <Text style={styles.textStyle}>
          Please insert any value to convert in SHA 256
        </Text>
        <TextInput
          style={styles.textInputStyle}
          onChangeText={
            (inputText) => setInputText(inputText)
          }
          placeholder="Enter Any Value"
          value={inputText}
        />
        <TouchableOpacity
          style={styles.buttonStyle}
          onPress={convertSHA}
        >
          <Text style={styles.buttonTextStyle}>
            Conver to SHA 256
          </Text>
        </TouchableOpacity>
      </View>
    </SafeAreaView>
  );
};
export default App;

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: 'white',
    justifyContent: 'center',
    padding: 10,
  },
  titleStyle: {
    fontSize: 20,
    textAlign: 'center',
    margin: 10,
  },
  textStyle: {
    textAlign: 'center',
    margin: 10,
  },
  textInputStyle: {
    flexDirection: 'row',
    height: 40,
    marginTop: 20,
    marginLeft: 35,
    marginRight: 35,
    margin: 10,
  },
  buttonStyle: {
    backgroundColor: '#51D8C7',
    borderWidth: 0,
    color: '#FFFFFF',
    borderColor: '#51D8C7',
    height: 40,
    alignItems: 'center',
    borderRadius: 5,
    marginLeft: 35,
    marginRight: 35,
    marginTop: 30,
  },
  buttonTextStyle: {
    color: '#FFFFFF',
    paddingVertical: 10,
    fontSize: 16,
  },
});

To Run the React Native App

Open the terminal again and jump into your project using.

cd ProjectName

1. Start Metro Bundler

First, you will need to start Metro, the JavaScript bundler that ships with React Native. To start Metro bundler run following command

npx react-native start

Once you start Metro Bundler it will run forever on your terminal until you close it. Let Metro Bundler run in its own terminal. Open a new terminal and run the application.

2. Start React Native Application

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

npx react-native run-android

or on the iOS Simulator by running (macOS only)

npx react-native run-ios

Download Source Code

Output Screenshots

      

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. 🙂