Here is an article on the subject:
Metamask: Calling ABI using Metamask's RPC provider from Web3.js
When working with decentralized applications (dApps) built on Ethereum, a common challenge is interacting with smart contracts hosted on the Ethereum network. One of the most convenient ways to do this is to use a tool like MetaMask, which provides an easy-to-use API for interacting with dApps via their web interfaces.
In your case, you want to call the balanceOf method from an ERC20 (Ethereum-based token) smart contract hosted on the Ethereum network. This requires you to use Web3.js and Metamask's RPC provider to make the call. Here's how you can do it:
Step 1: Set up your MetaMask account
First, make sure you have a MetaMask wallet installed and configured in your browser. If you don't already have a MetaMask account, follow these steps:
- Go to [MetaMask]( in your browser.
- Click the "Create New Wallet" button.
- Follow the instructions to create a new wallet.
Step 2: Install Web3.js and Configure Your MetaMask RPC Provider
To use Metamask's RPC provider, you will need to install Web3.js. You can do this by running the following command in your terminal:
npm install web3
After installing Web3.js, you need to configure your MetaMask account to provide an RPC endpoint for the Ethereum network.
- Go to [My Etherchain]( and create a new wallet.
- Click "Wallet" > "Add New Wallet".
- Follow the instructions to add your wallet to My Etherchain.
- In the settings, select "Web3 Provider" as your RPC endpoint. You can choose from different providers, such as Infura, Alchemy, or Localnode.
Step 3: Use Web3.js and Metamask's RPC provider to call balanceOf
Now that you've set up your MetaMask account with an RPC provider, it's time to use Web3.js to call the
method in your ERC20 smart contract. Here's a code example:const web3 = new Web3(new Web3.providers.HttpProvider('
// Select the Ethereum account associated with your MetaMask wallet
web3.eth.accounts.add('0x...');
// Call the balanceOf method from the ERC20 smart contract
web3.eth.call({
method: "balanceOf",
parameters: ['0x...'],
arguments: [],
}, (error, result) => {
if (error) throw error;
console.log(result);
});
In this example, we use the
eth.accounts.add' method to select the Ethereum account associated with your MetaMask wallet. Then, we call the balanceOf method of the ERC20 smart contract using the eth.call method of Web3.
Conclusion
With these steps, you have successfully used the Metamask RPC provider from Web3.js to call the balanceOf method from an ERC20 smart contract hosted on the Ethereum network. By following this guide, you can easily interact with dApps built on Ethereum using MetaMask and Web3.js.