Learn ETHERSJS with Real Code Examples

const { ethers } = require('ethers')

// Connect to local Ethereum node
const provider = new ethers.JsonRpcProvider('http://127.0.0.1:8545')

// Contract ABI and address
const abi = [...]
const address = '0xYourContractAddress'
const contract = new ethers.Contract(address, abi, provider)

// Read value from contract
async function main() {
    const value = await contract.getValue()
    console.log('Contract value:', value)

    // Send transaction to contract
    const signer = provider.getSigner(0)
    const tx = await contract.connect(signer).setValue(42)
    await tx.wait()
    console.log('Transaction complete')
}

main()

A minimal example showing how to connect to Ethereum and interact with a deployed smart contract using Ethers.js.

const { ethers } = require('ethers')
const provider = new ethers.JsonRpcProvider('http://127.0.0.1:8545')

async function main() {
    const balance = await provider.getBalance('0xYourAddress')
    console.log('Balance:', ethers.formatEther(balance))
}

main()

Connects to Ethereum and prints the Ether balance of an account.

const { ethers } = require('ethers')
const provider = new ethers.JsonRpcProvider('http://127.0.0.1:8545')

async function main() {
    const signer = provider.getSigner(0)
    const tx = await signer.sendTransaction({
        to: '0xRecipientAddress',
        value: ethers.parseEther('0.1')
    })
    await tx.wait()
    console.log('Ether sent')
}

main()

Send Ether from one account to another using Ethers.js.

const { ethers } = require('ethers')
const provider = new ethers.JsonRpcProvider('http://127.0.0.1:8545')
const signer = provider.getSigner(0)

async function main() {
    const factory = new ethers.ContractFactory(abi, bytecode, signer)
    const contract = await factory.deploy()
    await contract.deployed()
    console.log('Contract deployed at:', contract.address)
}

main()

Deploy a simple contract using Ethers.js and a signer.

const { ethers } = require('ethers')
const provider = new ethers.JsonRpcProvider('http://127.0.0.1:8545')
const contract = new ethers.Contract('0xYourContractAddress', abi, provider)

contract.on('ValueChanged', (newValue) => {
    console.log('Value changed:', newValue)
})

Subscribe to a contract event and log it in real-time.

const { ethers } = require('ethers')
const provider = new ethers.JsonRpcProvider('http://127.0.0.1:8545')
const contract = new ethers.Contract('0xYourContractAddress', abi, provider)

async function main() {
    const data = await contract.getData()
    console.log('Contract data:', data)
}

main()

Perform a read-only call to fetch contract data without sending a transaction.

const { ethers } = require('ethers')
const provider = new ethers.JsonRpcProvider('http://127.0.0.1:8545')
const contract = new ethers.Contract('0xYourContractAddress', abi, provider)

async function main() {
    const gasEstimate = await contract.estimateGas.setValue(42)
    console.log('Estimated gas:', gasEstimate)
}

main()

Estimate gas usage for a contract method call.

const { ethers } = require('ethers')
const provider = new ethers.JsonRpcProvider('http://127.0.0.1:8545')
const contract = new ethers.Contract('0xYourContractAddress', abi, provider)

async function main() {
    const value1 = await contract.getValue()
    const value2 = await contract.getAnotherValue()
    console.log('Values:', value1, value2)
}

main()

Use Ethers.js to make multiple contract calls in sequence.

const { ethers } = require('ethers')
const provider = new ethers.JsonRpcProvider('http://127.0.0.1:8545')

async function main() {
    const signer = provider.getSigner(0)
    const signature = await signer.signMessage('Hello Ethereum')
    console.log('Signature:', signature)
}

main()

Sign a message with an Ethereum account using Ethers.js.

const { ethers } = require('ethers')

const message = 'Hello Ethereum'
const signature = '0xSignatureHere'
const signerAddress = ethers.verifyMessage(message, signature)
console.log('Signer address:', signerAddress)

Verify an Ethereum signature using Ethers.js.