I have a front-end / web3 application that connects to a deployed contract in the rinkeby ethereum networt.
That is possible with the Web3 library, and creating an instance of web3, like the code below:
web3.js
import Web3 from "web3";
window.ethereum.request({ method: "eth_requestAccounts" });
const web3 = new Web3(window.ethereum);
export default web3;
So, in another file, i connect to the deployed contract via contract address and ABI:
contract.js
import web3 from "./web3";
const address = "0x(...)fEb";
const abi = ["(...)"]
export default new web3.eth.Contract(abi, address);
Ok. Then i can call methods on my etherium contract.
But i would like to do it in the mumbai polygon testnet. I already have a deployed / verified contract, and then in the contract.js, I replaced the values, address and abi, but it doesn't work.
I saw something about magic sdk library, but the examples is kind different from this model, and i got kind confused.
So, someone have a hint about how to connect to a mumbai polygon testnet to front-end?
If you need to communicate with Polygon, you should use Matic.js and use this guide: https://medium.com/the-polygon-blog/beginner-friendly-tutorial-to-matic-js-58f7c24c9744
Answer to the question: To connect to Mumbai Polygon you use:
const polygonNodeOptions = {
rpcUrl: 'https://rpc-mumbai.maticvigil.com/',
chainId: 80001,
};
From https://mumbai.polygonscan.com/tx/xxxxxx Get the contract address from your deployed contract. which you can find in To: section
then
const getContract = new web3.eth.Contract(yourabi, deployedcontractAddress); const res = await getContract.methods.your-method().call();
Hope this helps.
