transaction-models

Development

Work with Ethereum transaction types and models in Nethereum. Use when the user needs to create, decode, or inspect transactions (legacy, EIP-1559, EIP-2930, EIP-7702), work with Chain IDs, block headers, access lists, transaction recovery, or TransactionFactory.

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Transaction Models

NuGet: Nethereum.Model, Nethereum.Signer

Source: tests/Nethereum.Signer.UnitTests/ModelDocExampleTests.cs, tests/Nethereum.Signer.UnitTests/SignerDocExampleTests.cs

Legacy Transaction

using System.Numerics;
using Nethereum.Model;
using Nethereum.Hex.HexConvertors.Extensions;
using Nethereum.RLP;

var to = "0x13978aee95f38490e9769C39B2773Ed763d9cd5F";
var amount = BigInteger.Parse("10000000000000000"); // 0.01 ETH
var nonce = BigInteger.Zero;
var gasPrice = BigInteger.Parse("1000000000000");
var gasLimit = BigInteger.Parse("10000");

var tx = new LegacyTransaction(to, amount, nonce, gasPrice, gasLimit);
// tx.TransactionType == TransactionType.LegacyTransaction

EIP-1559 Transaction

var tx = new Transaction1559(
    chainId, nonce, maxPriorityFeePerGas, maxFeePerGas,
    gasLimit, receiverAddress, amount, data, accessList: null);
// tx.TransactionType == TransactionType.EIP1559

EIP-2930 Access List Transaction

using System.Collections.Generic;

var storageKey = new byte[32];
storageKey[31] = 0x01;
var accessList = new List<AccessListItem>
{
    new AccessListItem(contractAddress, new List<byte[]> { storageKey })
};

var tx = new Transaction2930(chainId, nonce, gasPrice, gasLimit,
    receiverAddress, amount, null, accessList);
// tx.TransactionType == TransactionType.LegacyEIP2930
// Uses gasPrice (like legacy) + access list + chainId

EIP-7702 Authorization Transaction

using Nethereum.Signer;

// 1. Create and sign authorization
var authorisation = new Authorisation7702(chainId, contractAddress, nonce);
var authSigner = new Authorisation7702Signer();
var signedAuth = authSigner.SignAuthorisation(ecKey, authorisation);

// 2. Create transaction with authorization list
var tx = new Transaction7702(
    chainId, nonce, maxPriorityFeePerGas, maxFeePerGas,
    gasLimit, receiverAddress, amount, null,
    new List<AccessListItem>(), new List<Authorisation7702Signed> { signedAuth });
// tx.TransactionType == TransactionType.EIP7702
// Uses EIP-1559 fee model + authorization list

Transaction Recovery

using Nethereum.Signer;

// Recover sender address from signed transaction RLP
var sender = TransactionVerificationAndRecovery.GetSenderAddress(signedRlpHex);

// Verify a signed transaction is valid
var isValid = TransactionVerificationAndRecovery.VerifyTransaction(signedRlpHex);

// Works with all tx types: Legacy, EIP-1559, EIP-2930, EIP-7702

Decode Transaction from RLP

var rlpBytes = rlpHex.HexToByteArray();
var tx = new LegacyTransaction(rlpBytes);
// tx.Nonce, tx.GasPrice, tx.Value, tx.ReceiveAddress, tx.Signature

TransactionFactory (Auto-Detection)

var decoded = TransactionFactory.CreateTransaction(signedRlpHex);
// Type prefix: 0x01=EIP-2930, 0x02=EIP-1559, 0x05=EIP-7702, none=Legacy

Chain Enum

Chain	ID	Enum Value
Mainnet	1	`Chain.MainNet`
Sepolia	11155111	`Chain.Sepolia`
Polygon	137	`Chain.Polygon`
Base	8453	`Chain.Base`

Transaction Type Table

Type	Prefix	Enum	Fee Model
Legacy	none	`TransactionType.LegacyTransaction`	gasPrice
Access List	0x01	`TransactionType.LegacyEIP2930`	gasPrice + accessList
EIP-1559	0x02	`TransactionType.EIP1559`	maxFeePerGas + maxPriorityFeePerGas
Blob	0x03	`TransactionType.Blob`	EIP-1559 + blobVersionedHashes
Set Code	0x05	`TransactionType.EIP7702`	EIP-1559 + authorisationList

Block Header

var blockHeader = new BlockHeader
{
    BlockNumber = 1000,
    GasLimit = 8000000,
    GasUsed = 21000,
    BaseFee = 1000000000,
    Coinbase = "0x0000000000000000000000000000000000000000"
};

AccessListItem

var item = new AccessListItem(address, new List<byte[]> { storageKey1, storageKey2 });
// item.Address, item.StorageKeys