Contract

Source code of this page

• source code link

import ConnectButton from '@/components/button/ConnectButton.vue'
import { shortenAddress, useVueDapp } from '@vue-dapp/core'
import { Interface, ethers } from 'ethers'

const defaultProvider = new ethers.JsonRpcProvider('https://arbitrum-sepolia-rpc.publicnode.com')
const supportedChainId = 421614
const supportedChainName = 'Arbitrum Sepolia'

// ======================== Contract ========================
const contractAddress = '0x4022Be091550EFB5dB2E5Ba93457ee69BF6e1aDA'

const iface = new Interface([
    'function retrieve() public view returns (uint256)',
    'function store(uint256 num)',
    'event Updated(address indexed addr, uint256 num)',
])

const contract = new ethers.Contract(contractAddress, iface, defaultProvider)

// ======================== Wallet ========================

const { isConnected, wallet, error: connectError } = useVueDapp()

onMounted(() => {
    fetchData()
    fetchEventLogs()

    // listen to events
    contract.on('Updated', (_addr, _num) => {
        fetchEventLogs()
    })
})

onUnmounted(() => {
    contract.removeAllListeners()
})

// ======================== Contract Read ========================
const error = ref(null)
const currentNum = ref(0)
const loading = ref(false)

async function fetchData() {
    error.value = null
    try {
        loading.value = true
        const data = Number(await contract.retrieve())
        currentNum.value = data
        newNum.value = data
        return data
    } catch (err: any) {
        error.value = err.message
    } finally {
        loading.value = false
    }
}

// ======================== Contract Write ========================
const newNum = ref(0)
const waiting = ref(false)

async function sendTransaction() {
    error.value = null

    try {
        waiting.value = true

        if (!isConnected.value) throw new Error('please connect your wallet first.')

        const provider = new ethers.BrowserProvider(wallet.provider!)
        const signer = await provider.getSigner()
        const tx = await (contract.connect(signer) as ethers.Contract).store(newNum.value)
        await tx.wait()

        fetchData()
        fetchEventLogs()
    } catch (err: any) {
        error.value = err
    } finally {
        waiting.value = false
    }
}

// ======================== Switch Chain ========================

async function switchChain() {
    const { connector } = useVueDapp()
    try {
        await connector.value?.switchChain?.(421614, {
            chainId: 421614,
            chainName: 'Arbitrum Sepolia',
            nativeCurrency: {
                symbol: 'ETH',
                decimals: 18,
            },
            rpcUrls: ['https://arbitrum-sepolia-rpc.publicnode.com/'],
            blockExplorerUrls: ['https://sepolia.arbiscan.io/'],
        })
    } catch (err: any) {
        error.value = err.message
    }
}

// ======================== Events ========================
const events = ref<ethers.EventLog[]>([])
const eventLoading = ref(false)

const displayEvents = computed(() => events.value.slice().reverse().slice(0, 3))

async function fetchEventLogs() {
    try {
        eventLoading.value = true

        // https://github.com/ethers-io/ethers.js/discussions/1816
        events.value = (await contract.queryFilter(contract.filters.Updated, -40000)) as ethers.EventLog[]
        console.log('events', events.value)
    } catch (err: any) {
        error.value = err.message
    } finally {
        eventLoading.value = false
    }
}

Contract source code

• Network: Arbitrum Sepolia
• Address: 0x4022Be091550EFB5dB2E5Ba93457ee69BF6e1aDA

// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.8.2 <0.9.0;

contract Storage {

    uint256 number;

    event Updated(address indexed addr, uint256 num);

    function store(uint256 num) public {
        number = num;
        emit Updated(msg.sender, num);
    }

    function retrieve() public view returns (uint256){
        return number;
    }
}

Foundry Cast to send the transaction

cast send --account dev \
  --rpc-url https://arbitrum-sepolia-rpc.publicnode.com \
    0x4022Be091550EFB5dB2E5Ba93457ee69BF6e1aDA \
    "function store(uint256 num)" \
    24