Building DApps on Binance Smart Chain

Tutorial 3 of 5

Introduction

This tutorial aims to guide you through the process of building decentralized applications (DApps) on the Binance Smart Chain (BSC). You will learn how to set up your development environment, create smart contracts, and interact with these contracts using frontend code.

What You Will Learn

The basics of Binance Smart Chain
How to set up your development environment
How to write and deploy smart contracts
How to interact with smart contracts from a DApp

Prerequisites

Basic understanding of blockchain and smart contracts
Familiarity with Solidity programming language
Basic understanding of JavaScript and web development

Step-by-Step Guide

1. Setting Up Development Environment

First, install Node.js and npm (Node Package Manager) which will be used to manage our development dependencies. You can download Node.js from here.

Next, install Truffle, a development environment, testing framework, and asset pipeline for Ethereum. Install it using npm:

npm install -g truffle

2. Creating a Truffle Project

Create a new directory for your project and initialize a new Truffle project:

mkdir my_dapp
cd my_dapp
truffle init

3. Writing a Smart Contract

In the contracts directory, create a new file called MyContract.sol. This contract will contain a simple function to store and retrieve a number:

// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;

contract MyContract {
    uint storedData;

    function set(uint x) public {
        storedData = x;
    }

    function get() public view returns (uint) {
        return storedData;
    }
}

4. Compiling and Deploying the Smart Contract

In the migrations directory, create a new file called 2_deploy_contracts.js:

const MyContract = artifacts.require("MyContract");

module.exports = function(deployer) {
  deployer.deploy(MyContract);
};

Then, compile and migrate the smart contract:

truffle compile
truffle migrate

Code Examples

Interacting with the Smart Contract

Create a new JavaScript file in the src directory:

const contract = require('truffle-contract');
const myContractJson = require('../build/contracts/MyContract.json');

const MyContract = contract(myContractJson);

MyContract.setProvider(web3.currentProvider);

MyContract.deployed().then(instance => {
  instance.set(10, {from: web3.eth.accounts[0]}).then(() => {
    return instance.get.call();
  }).then(result => {
    console.log(result.toNumber());
  });
});

This script sets the number 10 in the smart contract and then retrieves it.

Summary

In this tutorial, you learned how to set up your development environment, write a simple smart contract, deploy it to the Binance Smart Chain, and interact with it using JavaScript.

For further learning, consider exploring more complex smart contract examples and building a frontend interface for your DApp.

Practice Exercises

Write a smart contract that stores a string instead of a number.
Modify the JavaScript code to interact with the updated contract.
Build a simple web interface for your DApp.