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Erc-20 Tokens Development Tutorials, Guides & Insights

Unlock 3+ expert-curated erc-20 tokens tutorials, real-world code snippets, and modern dev strategies. From fundamentals to advanced topics, boost your erc-20 tokens skills on DeveloperBreeze.

How to Query ERC-20 Token Balances and Transactions Using Ethers.js and Etherscan API

Tutorial October 24, 2024

const axios = require('axios');

// Replace with your Etherscan API key
const apiKey = 'YOUR_ETHERSCAN_API_KEY';

// Replace with the wallet address you want to query
const address = '0xYourEthereumAddress';

// Replace with the ERC-20 token contract address
const contractAddress = '0xTokenContractAddress';

// Etherscan API URL to fetch ERC-20 token transactions
const url = `https://api.etherscan.io/api?module=account&action=tokentx&contractaddress=${contractAddress}&address=${address}&startblock=0&endblock=99999999&sort=asc&apikey=${apiKey}`;

async function getTokenTransactions() {
    try {
        // Make the API request to Etherscan
        const response = await axios.get(url);
        const transactions = response.data.result;

        // Log the token transactions
        transactions.forEach(tx => {
            console.log(`
                From: ${tx.from}
                To: ${tx.to}
                Value: ${ethers.utils.formatUnits(tx.value, 18)} Tokens
                Transaction Hash: ${tx.hash}
            `);
        });
    } catch (error) {
        console.error('Error fetching token transactions:', error);
    }
}

// Call the function to get the token transactions
getTokenTransactions();
  • API Key: Replace 'YOUR_ETHERSCAN_API_KEY' with the API key you generated from Etherscan.
  • Wallet Address: Replace '0xYourEthereumAddress' with the wallet address you want to query for token transactions.
  • Token Contract Address: Replace '0xTokenContractAddress' with the contract address of the ERC-20 token you want to track.

Sending Transactions and Interacting with Smart Contracts Using Infura and Ethers.js

Tutorial October 24, 2024

Deploying smart contracts is a more advanced topic, but here’s an example of how you can use Ethers.js with Infura to deploy a smart contract:

const ethers = require('ethers');

// Replace with your Infura Project ID
const infuraProvider = new ethers.JsonRpcProvider('https://mainnet.infura.io/v3/YOUR_INFURA_PROJECT_ID');

// Replace with your private key
const privateKey = 'YOUR_PRIVATE_KEY';

// Create a wallet instance and connect it to Infura
const wallet = new ethers.Wallet(privateKey, infuraProvider);

// Contract bytecode and ABI
const bytecode = '0xYourContractBytecode';
const abi = [
    // Your contract ABI here
];

async function deployContract() {
    try {
        // Create a ContractFactory to deploy the contract
        const factory = new ethers.ContractFactory(abi, bytecode, wallet);

        // Deploy the contract
        const contract = await factory.deploy();

        // Wait for the contract to be mined
        console.log('Contract deployed at address:', contract.address);
        await contract.deployTransaction.wait();
    } catch (error) {
        console.error('Error deploying contract:', error);
    }
}

// Call the function to deploy the contract
deployContract();

Understanding and Using the Etherscan API to Query Blockchain Data

Tutorial October 24, 2024

   https://api.etherscan.io/api?module=account&action=tokentx&address=0xYourEthereumAddress&startblock=0&endblock=99999999&sort=asc&apikey=YOUR_API_KEY
   https://api.etherscan.io/api?module=proxy&action=eth_gasPrice&apikey=YOUR_API_KEY