这是一篇文章的早期版本，旨在帮助那些对以太坊区块链平台有基本了解的开发人员，如果想学习如何使用Nethereum .NET库对Ethereum平台进行编程。
我以后会在这篇文章中添加更多内容，但就目前而言，正在使用它发布.NET 10+的系列C＃示例，介绍如何使用Nethereum库执行针对以太坊区块链平台的最常见任务。
最常见任务列表包括以下内容：
- 1.获取协议版本
- 2.获取最大块数
- 3.获取帐户余额
- 4.发送以太
- 5.等待交易收据
- 6.在区块链中扫描块
- 7.列出个人账户（及其余额）
- 8.在区块链中扫描交易
- 9.与现有（已部署）合同互动
- 10.用事件和现有（已部署）合约交互
- 11.获取所有活动更改
- 12.获取合约金额历史
这里是c#的主文件：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Nethereum.Hex.HexTypes;
using Nethereum.Web3;
namespace MWH.MyNethereum.QuickRef
{
static public class TaskExamples
{
const int UNLOCK_TIMEOUT = 2 * 60; // 2 minutes (arbitrary)
const int SLEEP_TIME = 5 * 1000; // 5 seconds (arbitrary)
const int MAX_TIMEOUT = 2 * 60 * 1000; // 2 minutes (arbirtrary)
// These static public variables do not represent a recommended pattern
static public string LastProtocolVersion = "";
static public string LastTxHash = "";
static public Nethereum.RPC.Eth.DTOs.TransactionReceipt LastTxReceipt = null;
static public HexBigInteger LastMaxBlockNumber = new HexBigInteger(0);
static public async Task GetProtocolVersionExample(Web3 web3)
{
Console.WriteLine("GetProtocolVersionExample:");
var protocolVersion = await web3.Eth.ProtocolVersion.SendRequestAsync();
Console.WriteLine("protocolVersion:\t" + protocolVersion.ToString());
LastProtocolVersion = protocolVersion;
}
static public async Task GetMaxBlockExample(Web3 web3)
{
Console.WriteLine("GetMaxBlockExample:");
var maxBlockNumber = await web3.Eth.Blocks.GetBlockNumber.SendRequestAsync();
Console.WriteLine("maxBlockNumber:\t" + maxBlockNumber.Value.ToString());
LastMaxBlockNumber = maxBlockNumber;
}
static public async Task ScanBlocksExample(Web3 web3, ulong startBlockNumber, ulong endBlockNumber)
{
Console.WriteLine("ScanBlocksExample:");
long txTotalCount = 0;
for (ulong blockNumber = startBlockNumber; blockNumber <= endBlockNumber; blockNumber++)
{
var blockParameter = new Nethereum.RPC.Eth.DTOs.BlockParameter(blockNumber);
var block = await web3.Eth.Blocks.GetBlockWithTransactionsByNumber.SendRequestAsync(blockParameter);
var trans = block.Transactions;
int txCount = trans.Length;
txTotalCount += txCount;
if (blockNumber % 1000 == 0) Console.Write(".");
if (blockNumber % 10000 == 0)
{
DateTime blockDateTime = Helpers.UnixTimeStampToDateTime((double)block.Timestamp.Value);
Console.WriteLine(blockNumber.ToString() + " " + txTotalCount.ToString() + " " + blockDateTime.ToString());
}
}
Console.WriteLine();
}
static public async Task ScanTxExample(Web3 web3, ulong startBlockNumber, ulong endBlockNumber)
{
Console.WriteLine("ScanTxExample:");
long txTotalCount = 0;
for (ulong blockNumber = startBlockNumber; blockNumber <= endBlockNumber; blockNumber++)
{
var blockParameter = new Nethereum.RPC.Eth.DTOs.BlockParameter(blockNumber);
var block = await web3.Eth.Blocks.GetBlockWithTransactionsByNumber.SendRequestAsync(blockParameter);
var trans = block.Transactions;
int txCount = trans.Length;
txTotalCount += txCount;
foreach (var tx in trans)
{
try
{
var bn = tx.BlockNumber.Value;
var th = tx.TransactionHash;
var ti = tx.TransactionIndex.Value;
var rpt = await web3.Eth.Transactions.GetTransactionReceipt.SendRequestAsync(th);
var status = rpt.Status.Value;
var nc = tx.Nonce.Value;
var from = tx.From;
Console.WriteLine(th.ToString() + " " + ti.ToString() + " " + from.ToString() + " " + status.ToString());
var to = tx.To;
if (to == null) to = "to:NULL";
var v = tx.Value.Value;
var g = tx.Gas.Value;
var gp = tx.GasPrice.Value;
Console.WriteLine(th.ToString() + " " + ti.ToString() + " " + nc.ToString() + " " + from.ToString() + " " + to.ToString() + " " + v.ToString() + " " + g.ToString() + " " + gp.ToString());
}
catch (Exception ex)
{
Console.WriteLine("ScanTxExample.Tx:\t" + ex.ToString());
if (ex.InnerException != null) Console.WriteLine("ScanTxExample.Tx:\t" + ex.InnerException.ToString());
}
}
Console.WriteLine();
}
}
static public async Task GetAccountBalanceExample(Web3 web3, string accountAddress)
{
Console.WriteLine("GetAccountBalanceExample:");
var balanceWei = await web3.Eth.GetBalance.SendRequestAsync(accountAddress);
var balanceEther = Web3.Convert.FromWei(balanceWei.Value);
Console.WriteLine("accountAddress:\t" + accountAddress.ToString());
Console.WriteLine("balanceEther:\t" + balanceEther.ToString());
}
static public async Task ListPersonalAccountsExample(Web3 web3)
{
Console.WriteLine("ListPersonalAccountsExample:");
var accounts = await web3.Personal.ListAccounts.SendRequestAsync();
foreach (var account in accounts)
{
var balanceWei = await web3.Eth.GetBalance.SendRequestAsync(account);
var balanceEther = Web3.Convert.FromWei(balanceWei.Value);
Console.WriteLine("account:\t" + account + " balanceEther:\t" + balanceEther.ToString());
}
}
static public async Task SendEtherExample(Web3 web3, string fromAddress, string fromPassword, string toAddress, long amountWei)
{
Console.WriteLine("SendEtherExample:");
var unlockResult = await web3.Personal.UnlockAccount.SendRequestAsync(fromAddress, fromPassword, UNLOCK_TIMEOUT);
var sendTxHash = await web3.Eth.TransactionManager.SendTransactionAsync(fromAddress, toAddress, new HexBigInteger(amountWei));
Console.WriteLine("fromAddress:\t" + fromAddress.ToString());
Console.WriteLine("toAddress:\t" + toAddress.ToString());
Console.WriteLine("amountWei:\t" + amountWei.ToString());
Console.WriteLine("sendTxHash:\t" + sendTxHash.ToString());
LastTxHash = sendTxHash;
}
static public async Task WaitForTxReceiptExample(Web3 web3, string txHash)
{
Console.WriteLine("WaitForTxReceiptExample:");
int timeoutCount = 0;
var txReceipt = await web3.Eth.Transactions.GetTransactionReceipt.SendRequestAsync(txHash);
while (txReceipt == null && timeoutCount < MAX_TIMEOUT)
{
Console.WriteLine("Sleeping...");
Thread.Sleep(SLEEP_TIME);
txReceipt = await web3.Eth.Transactions.GetTransactionReceipt.SendRequestAsync(txHash);
timeoutCount += SLEEP_TIME;
}
Console.WriteLine("timeoutCount " + timeoutCount.ToString());
LastTxReceipt = txReceipt;
}
static public async Task InteractWithExistingContractExample(Web3 web3, string fromAddress, string fromPassword, string contractAddress, string contractAbi)
{
Console.WriteLine("InteractWithExistingContractExample:");
var contract = web3.Eth.GetContract(contractAbi, contractAddress);
var setMessageFunction = contract.GetFunction("setMsg");
var getMessageFunction = contract.GetFunction("getMsg");
string nowTimestamp = DateTime.UtcNow.ToString() + " UTC";
Console.WriteLine("now:\t" + nowTimestamp);
var unlockResult = await web3.Personal.UnlockAccount.SendRequestAsync(fromAddress, fromPassword, UNLOCK_TIMEOUT);
var txHash1 = await setMessageFunction.SendTransactionAsync(fromAddress, new HexBigInteger(900000), null, 1, "Hello World");
Console.WriteLine("txHash1:\t" + txHash1.ToString());
var txHash2 = await setMessageFunction.SendTransactionAsync(fromAddress, new HexBigInteger(900000), null, 2, nowTimestamp);
Console.WriteLine("txHash2:\t" + txHash2.ToString());
var txReceipt2 = await web3.Eth.Transactions.GetTransactionReceipt.SendRequestAsync(txHash2);
int timeoutCount = 0;
while (txReceipt2 == null && timeoutCount < MAX_TIMEOUT)
{
Console.WriteLine("Sleeping...");
Thread.Sleep(SLEEP_TIME);
txReceipt2 = await web3.Eth.Transactions.GetTransactionReceipt.SendRequestAsync(txHash2);
timeoutCount += SLEEP_TIME;
}
Console.WriteLine("timeoutCount:\t" + timeoutCount.ToString());
var txReceipt3 = await setMessageFunction.SendTransactionAndWaitForReceiptAsync(fromAddress, new HexBigInteger(900000), null, null, 2, nowTimestamp + " Wait");
Console.WriteLine("txReceipt3:\t" + txReceipt3.TransactionHash.ToString());
Console.WriteLine("txReceipt3:\t" + txReceipt3.CumulativeGasUsed.Value.ToString());
var getResult1 = await getMessageFunction.CallAsync<string>(1);
Console.WriteLine("getResult1:\t" + getResult1.ToString());
var getResult2 = await getMessageFunction.CallAsync<string>(2);
Console.WriteLine("getResult2:\t" + getResult2.ToString());
}
static public async Task InteractWithExistingContractWithEventsExample(Web3 web3, string fromAddress, string fromPassword, string contractAddress, string contractAbi)
{
Console.WriteLine("InteractWithExistingContractWithEventsExample:");
var contract = web3.Eth.GetContract(contractAbi, contractAddress);
var setMessageFunction = contract.GetFunction("setMsg");
var getMessageFunction = contract.GetFunction("getMsg");
var multipliedEvent = contract.GetEvent("MultipliedEvent");
var newMessageEvent = contract.GetEvent("NewMessageEvent");
var filterAllMultipliedEvent = await multipliedEvent.CreateFilterAsync();
var filterAllNewMessageEvent = await newMessageEvent.CreateFilterAsync();
string nowTimestamp = DateTime.UtcNow.ToString() + " UTC";
Console.WriteLine("now:\t" + nowTimestamp);
var unlockResult = await web3.Personal.UnlockAccount.SendRequestAsync(fromAddress, fromPassword, UNLOCK_TIMEOUT);
var txHash1 = await setMessageFunction.SendTransactionAsync(fromAddress, new HexBigInteger(900000), null, 1, "Hello World");
Console.WriteLine("txHash1:\t" + txHash1.ToString());
var txHash2 = await setMessageFunction.SendTransactionAsync(fromAddress, new HexBigInteger(900000), null, 2, nowTimestamp);
Console.WriteLine("txHash2:\t" + txHash2.ToString());
var txReceipt2 = await web3.Eth.Transactions.GetTransactionReceipt.SendRequestAsync(txHash2);
int timeoutCount = 0;
while (txReceipt2 == null && timeoutCount < MAX_TIMEOUT)
{
Console.WriteLine("Sleeping...");
Thread.Sleep(SLEEP_TIME);
txReceipt2 = await web3.Eth.Transactions.GetTransactionReceipt.SendRequestAsync(txHash2);
timeoutCount += SLEEP_TIME;
}
Console.WriteLine("timeoutCount:\t" + timeoutCount.ToString());
var txReceipt3 = await setMessageFunction.SendTransactionAndWaitForReceiptAsync(fromAddress, new HexBigInteger(900000), null, null, 2, nowTimestamp + " Wait");
Console.WriteLine("txReceipt3:\t" + txReceipt3.TransactionHash.ToString());
Console.WriteLine("txReceipt3:\t" + txReceipt3.CumulativeGasUsed.Value.ToString());
var getResult1 = await getMessageFunction.CallAsync<string>(1);
Console.WriteLine("getResult1:\t" + getResult1.ToString());
var getResult2 = await getMessageFunction.CallAsync<string>(2);
Console.WriteLine("getResult2:\t" + getResult2.ToString());
var logMultipliedEvents = await multipliedEvent.GetFilterChanges<FunctionOutputHelpers.MultipliedEventArgs>(filterAllMultipliedEvent);
foreach (var mea in logMultipliedEvents)
{
Console.WriteLine("multipliedEvent:\t" +
mea.Event.sender + " " + mea.Event.oldProduct.ToString() + " " + mea.Event.value.ToString() + " " + mea.Event.newProduct.ToString());
}
var logNewMessageEvents = await newMessageEvent.GetFilterChanges<FunctionOutputHelpers.NewMessageEventArgs>(filterAllNewMessageEvent);
foreach (var mea in logNewMessageEvents)
{
Console.WriteLine("newMessageEvent:\t" +
mea.Event.sender + " " + mea.Event.ind.ToString() + " " + mea.Event.msg.ToString());
}
}
static public async Task GetAllChangesExample(Web3 web3, string fromAddress, string fromPassword, string contractAddress, string contractAbi)
{
Console.WriteLine("GetAllChangesExample:");
var contract = web3.Eth.GetContract(contractAbi, contractAddress);
var newMessageEvent = contract.GetEvent("NewMessageEvent");
var filterAllNewMessageEvent = await newMessageEvent.CreateFilterAsync(fromAddress);
var logNewMessageEvents = await newMessageEvent.GetAllChanges<FunctionOutputHelpers.NewMessageEventArgs>(filterAllNewMessageEvent);
foreach (var mea in logNewMessageEvents)
{
Console.WriteLine("newMessageEvent:\t" +
mea.Event.sender + " " + mea.Event.ind.ToString() + " " + mea.Event.msg.ToString());
}
}
static public async Task GetContractValuesHistoryUniqueOffsetValueExample(Web3 web3, string contractAddress, HexBigInteger recentBlockNumber, ulong numberBlocks, int offset)
{
Console.WriteLine("GetContractValuesHistoryUniqueOffsetValueExample:");
string previousValue = "";
for (ulong blockNumber = (ulong)recentBlockNumber.Value; blockNumber > (ulong)recentBlockNumber.Value - numberBlocks; blockNumber--)
{
var blockNumberParameter = new Nethereum.RPC.Eth.DTOs.BlockParameter(blockNumber);
var valueAtOffset = await web3.Eth.GetStorageAt.SendRequestAsync(contractAddress, new HexBigInteger(offset), blockNumberParameter);
if (valueAtOffset != previousValue)
{
var block = await web3.Eth.Blocks.GetBlockWithTransactionsByNumber.SendRequestAsync(blockNumberParameter);
DateTime blockDateTime = Helpers.UnixTimeStampToDateTime((double)block.Timestamp.Value);
Console.WriteLine("blockDateTime:\t" + blockDateTime.ToString());
for (int storageOffset = 0; storageOffset < offset+2; storageOffset++)
{
var valueAt = await web3.Eth.GetStorageAt.SendRequestAsync(contractAddress, new HexBigInteger(storageOffset), blockNumberParameter);
Console.WriteLine("value:\t" + blockNumber.ToString() + " " + storageOffset.ToString() + " " + valueAt + " " + Helpers.ConvertHex(valueAt.Substring(2)));
}
previousValue = valueAtOffset;
}
}
}
}
}以下是一些支持文件：
FunctionOutputHelpers.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Nethereum.Web3;
using Nethereum.ABI.FunctionEncoding.Attributes;
namespace MWH.MyNethereum.QuickRef
{
static public class FunctionOutputHelpers
{
// event MultipliedEvent(
// address indexed sender,
// int oldProduct,
// int value,
// int newProduct
// );
[FunctionOutput]
public class MultipliedEventArgs
{
[Parameter("address", "sender", 1, true)]
public string sender { get; set; }
[Parameter("int", "oldProduct", 2, false)]
public int oldProduct { get; set; }
[Parameter("int", "value", 3, false)]
public int value { get; set; }
[Parameter("int", "newProduct", 4, false)]
public int newProduct { get; set; }
}
//event NewMessageEvent(
// address indexed sender,
// uint256 indexed ind,
// string msg
//);
[FunctionOutput]
public class NewMessageEventArgs
{
[Parameter("address", "sender", 1, true)]
public string sender { get; set; }
[Parameter("uint256", "ind", 2, true)]
public int ind { get; set; }
[Parameter("string", "msg", 3, false)]
public string msg { get; set; }
}
}
}Helpers.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace MWH.MyNethereum.QuickRef
{
static public class Helpers
{
public static string ConvertHex(String hexString)
{
try
{
string ascii = string.Empty;
for (int i = 0; i < hexString.Length; i += 2)
{
String hs = string.Empty;
hs = hexString.Substring(i, 2);
uint decval = System.Convert.ToUInt32(hs, 16);
char character = System.Convert.ToChar(decval);
ascii += character;
}
return ascii;
}
catch (Exception ex) { Console.WriteLine(ex.Message); }
return string.Empty;
}
public static DateTime UnixTimeStampToDateTime(double unixTimeStamp)
{
// Unix timestamp is seconds past epoch
System.DateTime dtDateTime = new DateTime(1970, 1, 1, 0, 0, 0, 0, System.DateTimeKind.Utc);
dtDateTime = dtDateTime.AddSeconds(unixTimeStamp); // .ToLocalTime();
return dtDateTime;
}
public static DateTime JavaTimeStampToDateTime(double javaTimeStamp)
{
// Java timestamp is milliseconds past epoch
System.DateTime dtDateTime = new DateTime(1970, 1, 1, 0, 0, 0, 0, System.DateTimeKind.Utc);
dtDateTime = dtDateTime.AddMilliseconds(javaTimeStamp); // .ToLocalTime();
return dtDateTime;
}
}
}以下是用于实施这些示例时使用的以太坊合约的Solidity代码：
Test3.sol
pragma solidity 0.4.19;
contract Test3 {
int public _product;
string[5] _msgs;
event MultipliedEvent(
address indexed sender,
int oldProduct,
int value,
int newProduct
);
event NewMessageEvent(
address indexed sender,
uint256 indexed ind,
string msg
);
function Test3() public {
_product = 1;
}
function multiply(int value) public returns(int product) {
int old = _product;
_product = value * _product;
MultipliedEvent( msg.sender, old, value, _product );
return _product;
}
function getProduct() public constant returns(int product) {
return _product;
}
function setMsg(uint256 i, string m) public returns(uint256 mi) {
_msgs[i] = m;
NewMessageEvent( msg.sender, i, m);
return -i;
}
function getMsg(uint256 index) public constant returns(string m) {
return _msgs[index];
}
}我觉得这是发布代码示例的一种相当简单粗暴的方式。有任何更好建议欢迎留言。
如果你想马上使用c#开发以太坊dapp，可以学习下面的教程：
C#以太坊，主要讲解如何使用C#开发基于.Net的以太坊应用，包括账户管理、状态与交易、智能合约开发与交互、过滤器和事件等。
这里是原文
