client封装总体框架
client编程基于堵塞同步模式，仅仅有数据正常发送或接收才返回，假设错误发生则抛出异常，基于TcpClient进行封装，主要类结构例如以下图：
TcpClient：NET系统封装，实现了底层Socket操作，提供了堵塞和非堵塞调用；
OutgoingDataAssembler m_outgoingDataAssembler：协议组装器，用来组装往外发送的命令，主要用于组装协议格式；
DynamicBufferManager m_sendBuffer：用于把命令和数据同一时候写入到缓存中，调用一次发送，这样server就仅仅会产生一次IOCP回调，能够提高性能；
IncomingDataParser m_incomingDataParser：收到数据的解析器，用于解析返回的内容，主要是解析文本格式；
protected DynamicBufferManager m_recvBuffer：接收数据的缓存，数据存到缓存中后，能够解析命令和数据；
TcpClient说明，堵塞和非堵塞
TcpClient封装了NET的底层Socket操作，基于TCP协议，提供了堵塞和非堵塞模式调用，详细是设置m_tcpClient.Client.Blocking = true表示使用堵塞模式，反之则使用非堵塞模式。堵塞模式表示接收完指定长度的数据才返回，非堵塞模式表示收到一点数据就返回。
如我们调用m_tcpClient.Client.Receive(m_recvBuffer.Buffer, sizeof(int), packetLength, SocketFlags.None)，如果传入的长度为1024，堵塞模式一点要等到数据达到1024长度才返回，否则一直等待Socket超时或者链路断了，非堵塞模式则不同，增加收到8字节了，则返回调用者，调用者使用循环继续接受1024-8=1016的数据。
发送命令
发送数据和服务端同样，主要是对数据进行组包，然后调用发送函数发送，详细代码例如以下：
public void SendCommand(byte[] buffer, int offset, int count) { string commandText = m_outgoingDataAssembler.GetProtocolText(); byte[] bufferUTF8 = Encoding.UTF8.GetBytes(commandText); int totalLength = sizeof(int) + bufferUTF8.Length + count; //获取总大小 m_sendBuffer.Clear(); m_sendBuffer.WriteInt(totalLength, false); //写入总大小 m_sendBuffer.WriteInt(bufferUTF8.Length, false); //写入命令大小 m_sendBuffer.WriteBuffer(bufferUTF8); //写入命令内容 m_sendBuffer.WriteBuffer(buffer, offset, count); //写入二进制数据 m_tcpClient.Client.Send(m_sendBuffer.Buffer, 0, m_sendBuffer.DataCount, SocketFlags.None); }
接收命令
接收命令和发送相反，先接收长度，然后接收内容，然后对数据进行解包，详细代码例如以下：
public bool RecvCommand(out byte[] buffer, out int offset, out int size) { m_recvBuffer.Clear(); m_tcpClient.Client.Receive(m_recvBuffer.Buffer, sizeof(int), SocketFlags.None); int packetLength = BitConverter.ToInt32(m_recvBuffer.Buffer, 0); //获取包长度 if (NetByteOrder) packetLength = System.Net.IPAddress.NetworkToHostOrder(packetLength); //把网络字节顺序转为本地字节顺序 m_recvBuffer.SetBufferSize(sizeof(int) + packetLength); //保证接收有足够的空间 m_tcpClient.Client.Receive(m_recvBuffer.Buffer, sizeof(int), packetLength, SocketFlags.None); int commandLen = BitConverter.ToInt32(m_recvBuffer.Buffer, sizeof(int)); //取出命令长度 string tmpStr = Encoding.UTF8.GetString(m_recvBuffer.Buffer, sizeof(int) + sizeof(int), commandLen); if (!m_incomingDataParser.DecodeProtocolText(tmpStr)) //解析命令 { buffer = null; offset = 0; size = 0; return false; } else { buffer = m_recvBuffer.Buffer; offset = commandLen + sizeof(int) + sizeof(int); size = packetLength - offset; return true; } }
命令交互
封装了底层Socket操作和协议解析后，实现一个命令交互如登录代码例如以下：
public bool DoLogin(string userName, string password) { try { m_outgoingDataAssembler.Clear(); m_outgoingDataAssembler.AddRequest(); m_outgoingDataAssembler.AddCommand(AsyncSocketServer.ProtocolKey.Login); m_outgoingDataAssembler.AddValue(AsyncSocketServer.ProtocolKey.UserName, userName); m_outgoingDataAssembler.AddValue(AsyncSocketServer.ProtocolKey.Password, AsyncSocketServer.BasicFunc.MD5String(password)); SendCommand(); bool bSuccess = RecvCommand(); if (bSuccess) { bSuccess = CheckErrorCode(); if (bSuccess) { m_userName = userName; m_password = password; } return bSuccess; } else return false; } catch (Exception E) { //记录日志 m_errorString = E.Message; return false; } }
上传协议
上传协议主要分为三个命令，第一个是Upload，向server请求上传的文件，假设server有同样的文件，则返回是否传完，假设未传完，返回须要续传的文件位置，然后client则从上一个位置開始传输，数据传输server仅仅接收，不应答，client传输完后，发完毕（EOF）命令。因此三个命令封装代码例如以下：
public bool DoUpload(string dirName, string fileName, ref long fileSize) { bool bConnect = ReConnectAndLogin(); //检測连接是否还在，假设断开则重连并登录 if (!bConnect) return bConnect; try { m_outgoingDataAssembler.Clear(); m_outgoingDataAssembler.AddRequest(); m_outgoingDataAssembler.AddCommand(AsyncSocketServer.ProtocolKey.Upload); m_outgoingDataAssembler.AddValue(AsyncSocketServer.ProtocolKey.DirName, dirName); m_outgoingDataAssembler.AddValue(AsyncSocketServer.ProtocolKey.FileName, fileName); SendCommand(); bool bSuccess = RecvCommand(); if (bSuccess) { bSuccess = CheckErrorCode(); if (bSuccess) { bSuccess = m_incomingDataParser.GetValue(AsyncSocketServer.ProtocolKey.FileSize, ref fileSize); } return bSuccess; } else return false; } catch (Exception E) { //记录日志 m_errorString = E.Message; return false; } } public bool DoData(byte[] buffer, int offset, int count) { try { m_outgoingDataAssembler.Clear(); m_outgoingDataAssembler.AddRequest(); m_outgoingDataAssembler.AddCommand(AsyncSocketServer.ProtocolKey.Data); SendCommand(buffer, offset, count); return true; } catch (Exception E) { //记录日志 m_errorString = E.Message; return false; } } public bool DoEof(Int64 fileSize) { try { m_outgoingDataAssembler.Clear(); m_outgoingDataAssembler.AddRequest(); m_outgoingDataAssembler.AddCommand(AsyncSocketServer.ProtocolKey.Eof); SendCommand(); bool bSuccess = RecvCommand(); if (bSuccess) return CheckErrorCode(); else return false; } catch (Exception E) { //记录日志 m_errorString = E.Message; return false; } }调用过程：protected static bool SendFile(string fileName, ClientUploadSocket uploadSocket) { FileStream fileStream = new FileStream(fileName, FileMode.Open, FileAccess.ReadWrite); try { try { long fileSize = 0; if (!uploadSocket.DoUpload("", Path.GetFileName(fileName), ref fileSize)) throw new Exception(uploadSocket.ErrorString); fileStream.Position = fileSize; byte[] readBuffer = new byte[PacketSize]; while (fileStream.Position < fileStream.Length) { int count = fileStream.Read(readBuffer, 0, PacketSize); if (!uploadSocket.DoData(readBuffer, 0, count)) throw new Exception(uploadSocket.ErrorString); } if (!uploadSocket.DoEof(fileStream.Length)) throw new Exception(uploadSocket.ErrorString); return true; } catch (Exception E) { Console.WriteLine("Upload File Error: " + E.Message); return false; } } finally { fileStream.Close(); } }
DEMO下载地址：http://download.csdn.net/detail/sqldebug_fan/7467745
免责声明：此代码仅仅是为了演示C#完毕port编程，仅用于学习和研究，切勿用于商业用途。水平有限，C#也属于初学，错误在所难免，欢迎指正和指导。邮箱地址：fansheng_hx@163.com。