web3.js

Conéctese a 256 Blocks usando web3.js

web3.js es la API JavaScript original de Ethereum, proporcionando una colección de bibliotecas para interactuar con nodos de Ethereum. Esta guía cubre web3.js v4.

Instalación

npm install web3

O con yarn:

yarn add web3

Inicio Rápido

Conéctese a 256 Blocks usando el encabezado X-API-Key con HttpProvider:

import { Web3, HttpProvider } from 'web3';
 
// Configure provider with custom headers
const httpOptions = {
  providerOptions: {
    headers: {
      'X-API-Key': 'your-api-key'
    }
  }
};
 
// Create the provider and Web3 instance
const provider = new HttpProvider('https://rpc.256blocks.com/ethereum', httpOptions);
const web3 = new Web3(provider);
 
// Get the latest block number
const blockNumber = await web3.eth.getBlockNumber();
console.log('Latest block:', blockNumber);

Lectura del Saldo de una Cuenta

import { Web3, HttpProvider } from 'web3';
 
const httpOptions = {
  providerOptions: {
    headers: {
      'X-API-Key': 'your-api-key'
    }
  }
};
 
const provider = new HttpProvider('https://rpc.256blocks.com/ethereum', httpOptions);
const web3 = new Web3(provider);
 
// Get account balance
const address = '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb';
const balance = await web3.eth.getBalance(address);
 
console.log('Balance:', web3.utils.fromWei(balance, 'ether'), 'ETH');

Lectura de Datos de Contratos

import { Web3, HttpProvider } from 'web3';
 
const httpOptions = {
  providerOptions: {
    headers: {
      'X-API-Key': 'your-api-key'
    }
  }
};
 
const provider = new HttpProvider('https://rpc.256blocks.com/ethereum', httpOptions);
const web3 = new Web3(provider);
 
// ERC-20 ABI (minimal)
const erc20Abi = [
  {
    name: 'balanceOf',
    type: 'function',
    stateMutability: 'view',
    inputs: [{ name: 'account', type: 'address' }],
    outputs: [{ name: '', type: 'uint256' }]
  },
  {
    name: 'decimals',
    type: 'function',
    stateMutability: 'view',
    inputs: [],
    outputs: [{ name: '', type: 'uint8' }]
  }
];
 
// USDC contract on Ethereum
const usdcAddress = '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48';
const contract = new web3.eth.Contract(erc20Abi, usdcAddress);
 
const balance = await contract.methods.balanceOf('0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb').call();
const decimals = await contract.methods.decimals().call();
 
// Convert balance to human-readable format
const formattedBalance = Number(balance) / Math.pow(10, Number(decimals));
console.log('USDC Balance:', formattedBalance);

Soporte Multi-Cadena

Conéctese a diferentes cadenas cambiando el endpoint:

import { Web3, HttpProvider } from 'web3';
 
function createWeb3(chain, apiKey) {
  const httpOptions = {
    providerOptions: {
      headers: {
        'X-API-Key': apiKey
      }
    }
  };
 
  const provider = new HttpProvider(`https://rpc.256blocks.com/${chain}`, httpOptions);
  return new Web3(provider);
}
 
// Create Web3 instances for different chains
const ethWeb3 = createWeb3('ethereum', 'your-api-key');
const baseWeb3 = createWeb3('base', 'your-api-key');
const arbWeb3 = createWeb3('arbitrum', 'your-api-key');
const polygonWeb3 = createWeb3('polygon', 'your-api-key');

Recursos

web3.js | 256 Blocks