A guide to developing smart contracts and blockchain applications using Vue.js and JavaScript

A guide to developing smart contracts and blockchain applications using Vue.js and JavaScript

Introduction:
With the development of blockchain technology, Ethereum, as a smart contract platform, provides a platform for development The staff provided a great convenience. Vue.js, as a popular JavaScript framework, provides developers with powerful front-end technical support. This article will provide a guide on how to use Vue.js and JavaScript to develop smart contracts and blockchain applications, with code examples.

1. Environment preparation
   Before starting development, we need to ensure that the preparation of the local environment has been completed. First, install Node.js and npm (Node.js package manager), you can download and install the latest version from the official website. Then, run the following command via the command line tool to verify that the installation was successful:

node -v
npm -v

2. Create Vue.js Project
   We will use the Vue CLI command line tool to create a new Vue.js project. Open the command line tool and run the following command:

npm install -g @vue/cli
vue create blockchain-app
cd blockchain-app

The above command will install the Vue CLI globally and create a new Vue.js project in the project folder. Then switch to the project folder.

3. Install web3.js
   To interact with the Ethereum blockchain, we need to use the web3.js library. Run the following command to install web3.js:

npm install web3

4. Connect to the Ethereum blockchain
   Create a web3 instance in Vuex to connect to the Ethereum blockchain. Open the src/store/index.js file and import web3 at the top of the file:

import Web3 from 'web3';

Then, add a file named properties of web3 and set it to null: <div class="code" style="position:relative; padding:0px; margin:0px;"><pre class='brush:php;toolbar:false;'>state: { web3: null },</pre><div class="contentsignin">Copy after login</div></div>Next, add a method named

registerWeb3

in mutations, This method will be responsible for creating the web3 instance and storing it in Vuex's state: <div class="code" style="position:relative; padding:0px; margin:0px;"><pre class='brush:php;toolbar:false;'>mutations: { registerWeb3(state, payload) { state.web3 = payload.web3; } },</pre><div class="contentsignin">Copy after login</div></div>Finally, add a file called

initWeb3# in

actions ## method, which will be responsible for connecting to the Ethereum blockchain and calling the registerWeb3 method:

actions: {
  initWeb3({ commit }) {
    if (typeof web3 !== 'undefined') {
      web3 = new Web3(web3.currentProvider);
      commit('registerWeb3', { web3 });
    } else {
      console.error('No web3 provider detected');
    }
  }
},

Smart Contract Interaction

Next, we will The component calls the methods of the smart contract and interacts with the Ethereum blockchain. Create a property named

contract
5. in the Vue component, and call the smart contract method in the
   created life cycle hook: <div class="code" style="position:relative; padding:0px; margin:0px;"><pre class='brush:php;toolbar:false;'>import contractABI from '@/contracts/ContractABI.json'; import contractAddress from '@/contracts/ContractAddress.json'; export default { data() { return { contract: null }; }, created() { this.contract = new web3.eth.Contract(contractABI, contractAddress); }, methods: { async getContractData() { const result = await this.contract.methods.getData().call(); console.log(result); }, async setContractData() { await this.contract.methods.setData('Hello, blockchain!').send({ from: web3.eth.defaultAccount }); console.log('Transaction completed'); } } }</pre><div class="contentsignin">Copy after login</div></div>In the above code , we first import the ABI (Application Binary Interface) and address of the smart contract. Then, in the
created

lifecycle hook, we use this information to create a new smart contract instance.

In the methods

of the Vue component, we define two methods:

getContractData and setContractData, which are used to call the smart contract methods and Interact with the Ethereum blockchain. Code Example

Finally, we use the button in the template of the Vue component to call the smart contract method. Edit the

src/views/Home.vue
6. file and add the following code:
   <div class="code" style="position:relative; padding:0px; margin:0px;"><pre class='brush:php;toolbar:false;'>&lt;template&gt; &lt;div&gt; &lt;button @click=&quot;getContractData&quot;&gt;Get Data&lt;/button&gt; &lt;button @click=&quot;setContractData&quot;&gt;Set Data&lt;/button&gt; &lt;/div&gt; &lt;/template&gt;</pre><div class="contentsignin">Copy after login</div></div>The above code adds two buttons to the template of the Vue component and calls
getContractData respectively.

and

setContractData methods. Summary: This article introduces a guide to developing smart contracts and blockchain applications using Vue.js and JavaScript. We first prepared the development environment and created a new Vue.js project. Then, connect to the Ethereum blockchain through the web3.js library, and call the smart contract's methods in the Vue component and interact with the blockchain. Through this guide, developers already have the basic knowledge and skills to develop smart contracts and blockchain applications using Vue.js and JavaScript.

Appendix: Complete code example

// src/store/index.js
import Web3 from 'web3';

export default {
  state: {
    web3: null
  },
  mutations: {
    registerWeb3(state, payload) {
      state.web3 = payload.web3;
    }
  },
  actions: {
    initWeb3({ commit }) {
      if (typeof web3 !== 'undefined') {
        web3 = new Web3(web3.currentProvider);
        commit('registerWeb3', { web3 });
      } else {
        console.error('No web3 provider detected');
      }
    }
  }
}

// src/views/Home.vue
import contractABI from '@/contracts/ContractABI.json';
import contractAddress from '@/contracts/ContractAddress.json';

export default {
  data() {
    return {
      contract: null
    };
  },
  created() {
    this.contract = new web3.eth.Contract(contractABI, contractAddress);
  },
  methods: {
    async getContractData() {
      const result = await this.contract.methods.getData().call();
      console.log(result);
    },
    async setContractData() {
      await this.contract.methods.setData('Hello, blockchain!').send({ from: web3.eth.defaultAccount });
      console.log('Transaction completed');
    }
  }
}

I hope this article will be helpful to beginners who use Vue.js and JavaScript to develop smart contracts and blockchain applications. Further learning and development can be carried out according to actual needs.

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