Query data & submit a transaction with web3dart

query_submit.dart

Future<String> submit(String functionName, List<dynamic> args) async {
    EthPrivateKey credentials = EthPrivateKey.fromHex(
        "3d272d3193203d7a4458ea2a38ace936075c776512fc27093597ca2c790602a9");

    DeployedContract contract = await loadContract();

    final ethFunction = contract.function(functionName);

    var result = await ethClient.sendTransaction(
      credentials,
      Transaction.callContract(
        contract: contract,
        function: ethFunction,
        parameters: args,
      ),
    );
    return result;
  }

  Future<List<dynamic>> query(String functionName, List<dynamic> args) async {
    final contract = await loadContract();
    final ethFunction = contract.function(functionName);
    final data = await ethClient.call(
        contract: contract, function: ethFunction, params: args);
    return data;
  }