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Generate C# from Solidity

After compiling your Solidity contracts with forge build, the next step is generating typed C# services so your .NET code can deploy, call, and query contracts without manual ABI handling. The dApp template includes generation scripts and ships with pre-generated code so you can build immediately.

How It Works​

The flow is:

contracts/src/MyToken.sol
        ↓ forge build
contracts/out/MyToken.sol/MyToken.json    (ABI + bytecode)
        ↓ generate-csharp script
ContractServices/MyToken/
├── ContractDefinition/MyTokenDefinition.gen.cs   (function/event messages)
└── MyTokenService.gen.cs                          (typed service class)

The generated MyTokenService gives you strongly-typed methods for every contract function — deploy, mint, transfer, balanceOf, etc. — with proper C# types, async/await, and receipt handling.

Run Code Generation​

After modifying Solidity and running forge build:

Windows (PowerShell):

pwsh scripts/generate-csharp.ps1

Linux/macOS:

bash scripts/generate-csharp.sh

Both scripts accept a -b flag to run forge build first:

pwsh scripts/generate-csharp.ps1 -b

The scripts use Nethereum.Generator.Console with the configuration in contracts/.nethereum-gen.multisettings to read the Foundry output and generate C# into ContractServices/.

What Gets Generated​

For each contract, you get two files:

ContractDefinition (messages)​

ContractServices/MyToken/ContractDefinition/MyTokenDefinition.gen.cs contains:

  • Deployment message — MyTokenDeployment with constructor parameters
  • Function messages — MintFunction, TransferFunction, BalanceOfFunction, etc.
  • Event DTOs — TransferEventDTO, ApprovalEventDTO
  • Output DTOs — BalanceOfOutputDTO, NameOutputDTO, etc.

Each message is a C# class with properties matching the Solidity function parameters, fully typed (e.g., BigInteger for uint256, string for address).

Service (typed methods)​

ContractServices/MyToken/MyTokenService.gen.cs provides:

// Deploy
var receipt = await MyTokenService.DeployContractAndWaitForReceiptAsync(web3, deployment);

// Query (read-only, no gas)
var name = await tokenService.NameQueryAsync();
var balance = await tokenService.BalanceOfQueryAsync(ownerAddress);

// Write (sends transaction)
var receipt = await tokenService.MintRequestAndWaitForReceiptAsync(toAddress, amount);
var receipt = await tokenService.TransferRequestAndWaitForReceiptAsync(toAddress, amount);

Every write method has both RequestAsync (returns tx hash) and RequestAndWaitForReceiptAsync (waits for mining) variants.

Using Generated Services​

Here's a complete example from the template's TDD tests:

// Create an in-process DevChain
var node = await DevChainNode.CreateAndStartAsync();
var web3 = node.CreateWeb3(DevChainAccounts.Account2.PrivateKey);

// Deploy
var deployment = new MyTokenDeployment
{
    Name = "TestToken",
    Symbol = "TT",
    InitialSupply = Web3.Convert.ToWei(1_000_000)
};
var receipt = await MyTokenService.DeployContractAndWaitForReceiptAsync(web3, deployment);
var tokenService = new MyTokenService(web3, receipt.ContractAddress);

// Query
var name = await tokenService.NameQueryAsync();     // "TestToken"
var supply = await tokenService.TotalSupplyQueryAsync(); // 1_000_000 * 10^18

// Mint
await tokenService.MintRequestAndWaitForReceiptAsync(
    "0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266",
    Web3.Convert.ToWei(100));

// Transfer
await tokenService.TransferRequestAndWaitForReceiptAsync(
    "0x70997970C51812dc3A010C7d01b50e0d17dc79C8",
    Web3.Convert.ToWei(50));

Adding a New Contract​

When you add a new .sol file (as shown in Write Contracts):

  1. Compile: cd contracts && forge build
  2. Regenerate: pwsh scripts/generate-csharp.ps1
  3. The new service appears in ContractServices/YourContract/
  4. Add a <Compile Include="..." /> or rely on wildcard includes in ContractServices.csproj

Next Steps​

With typed C# services in hand: