Erc-20 Tokens Development Tutorials, Guides & Insights

By the end of this tutorial, you will be able to:

• Query the balance of ERC-20 tokens for an Ethereum address.
• Retrieve ERC-20 token transfer histories using the Etherscan API.

• Node.js installed on your machine.
• A basic understanding of JavaScript and blockchain concepts.
• An Ethereum wallet with some test ETH (using testnets like Goerli or Ropsten is recommended for testing).
• An Infura Project ID to access the Ethereum network.

If you don't have an Infura account yet, follow these steps:

const axios = require('axios');

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

// Replace this with the transaction hash you want to query
const transactionHash = '0xYourTransactionHash';

// Etherscan API URL to fetch transaction details
const url = `https://api.etherscan.io/api?module=proxy&action=eth_getTransactionByHash&txhash=${transactionHash}&apikey=${apiKey}`;

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

    // Log the transaction details
    console.log('Transaction Details:', transactionDetails);
  } catch (error) {
    console.error('Error fetching transaction details:', error);
  }
}

// Call the function to get the transaction details
getTransactionDetails();

• Replace 'YOUR_ETHERSCAN_API_KEY' with your actual Etherscan API key.
• Replace '0xYourTransactionHash' with the transaction hash you want to query.
• This script uses the eth_getTransactionByHash endpoint to fetch transaction details, such as gas price, block number, and sender/receiver addresses.