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Usage

caution

The Web3Modal SDK for Unity is currently in Alpha. Breaking changes may occur in future versions.

After you have installed and configured Web3Modal, you can start using it to interact with the wallet provider and blockchain.

Web3Modal comes with the Nethereum integration out of the box. You can use it to interact with the EVM chains, smart contracts, convert between different units, etc.

An instance of Nethereum's Web3 class is available in the Web3Modal at Web3Modal.Web3. It's already preconfigured with RPC URL and interceptor that will route the requests between the wallet provider and RPC node.

Warning

Under some circumstances, Web3Modal may create a new instance of Web3 class with a different configuration. Therefore, refrain from caching a reference to the Web3 instance and always use Web3Modal.Web3 to access it.

// ❌ Don't do this
var web3 = Web3Modal.Web3;
await web3.Eth.Blocks.GetBlockNumber.SendRequestAsync();

// ✅ Instead, always use
await Web3Modal.Web3.Eth.Blocks.GetBlockNumber.SendRequestAsync();
Learn More About Nethereum

Sending Ether​

To send ether, you can use the SendTransactionAsync method of the Web3.Eth class.

const string toAddress = "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045";
await Web3Modal.Web3.Eth
    .GetEtherTransferService()
    .TransferEtherAndWaitForReceiptAsync(toAddress, 0.00001m); // 0.00001 ETH

This type of transaction uses the default amount of Gas 21000. Gas price is determined by the wallet provider. It's possible to specify the gas price and gas limit manually. Refer to the Nethereum documentation for more information.

Reading Blockchain State​

Get Ether Balance​

var account = Web3Modal.GetAccount();
var balance = await Web3Modal.Web3.Eth.GetBalance.SendRequestAsync(account.Address);

Debug.Log($"Balance: {Web3.Convert.FromWei(balance.Value)} ETH");

Smart Contract Interaction​

It's possible to interact with smart contracts using Web3Modal.Web3.Eth. It comes with a set of popular contract services like ERC20, ERC721, etc. You can use them to interact with the smart contracts without any additional setup.

Get ERC20 Token Balance​

To get the balance of an ERC20 token, you need to know the contract address and the owner address. This operation doesn't involve state change on the blockchain, so it's a read-only action that doesn't require a transaction.

const string contractAddress = "0x1f9840a85d5aF5bf1D1762F925BDADdC4201F984";
const string ownerAddress = "0x3D30B1aB88D487B0F3061F40De76845Bec3F1e94";

var contractService = Web3Modal.Web3.Eth.ERC20.GetContractService(contractAddress);

var tokenBalance = await contractService.BalanceOfQueryAsync(ownerAddress);
var tokenDecimal = await contractService.DecimalsQueryAsync();

var finalBalance = tokenBalance / BigInteger.Pow(10, tokenDecimal);

Send ERC20 Token​

To send an ERC20 token, you need to know the contract address, recipient address, and the amount of tokens to send. This operation requires a transaction and gas fees because it changes the state of the blockchain. User will need to confirm the transaction in the wallet.

const string contractAddress = "0x1f9840a85d5aF5bf1D1762F925BDADdC4201F984";
const string recipientAddress = "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045";
const BigInteger amount = 1;

var contractService = Web3Modal.Web3.Eth.ERC20.GetContractService(contractAddress);

await contractService.TransferRequestAsync(recipientAddress, amount);

Interact with Custom Smart Contracts​

Nethereum allows to deploy and interact with custom smart contracts as well. Refer to the Nethereum documentation for more information.