介绍
在阅读了罗培羽著作的Unity3D网络游戏实战一书后，博主综合自己的开发经验与考虑进行部分修改和调整，将通用的客户端网络模块和通用的服务端框架进行提取，形成专栏，介绍Socket网络编程，希望对其他人有所帮助。目录如下，链接为对应的CSDN博客地址：
一、通用服务端框架
（一）、定义套接字和多路复用
https://blog.csdn.net/qq_42139931/article/details/124051945?spm=1001.2014.3001.5501
（二）、客户端信息类和通用缓冲区结构
https://blog.csdn.net/qq_42139931/article/details/124053571?spm=1001.2014.3001.5502
（三）、Protobuf 通信协议
https://blog.csdn.net/qq_42139931/article/details/124054972?spm=1001.2014.3001.5501
（四）、数据处理和关闭连接
https://blog.csdn.net/qq_42139931/article/details/124055227?spm=1001.2014.3001.5501
（五）、Messenger 事件发布、订阅系统
https://blog.csdn.net/qq_42139931/article/details/124055392?spm=1001.2014.3001.5501
（六）、单点发送和广播数据
https://blog.csdn.net/qq_42139931/article/details/124055482?spm=1001.2014.3001.5501
（七）、时间戳和心跳机制
https://blog.csdn.net/qq_42139931/article/details/124055856?spm=1001.2014.3001.5501
二、通用客户端网络模块
（一）、Connect 连接服务端
https://blog.csdn.net/qq_42139931/article/details/124091349?spm=1001.2014.3001.5502
（二）、Receive 接收并处理数据
https://blog.csdn.net/qq_42139931/article/details/124092588?spm=1001.2014.3001.5502
（三）、Send 发送数据
https://blog.csdn.net/qq_42139931/article/details/124094323?spm=1001.2014.3001.5502
（四）、Close 关闭连接
https://blog.csdn.net/qq_42139931/article/details/124094895?spm=1001.2014.3001.5502
本篇内容：
Receive 接收数据：
连接服务端成功后调用socket.BeginReceive开始接收数据：
代码语言：javascript复制//Connect回调
private static void ConnectCallback(IAsyncResult ar)
{
try
{
Socket socket = (Socket)ar.AsyncState;
socket.EndConnect(ar);
isConnecting = false;
Debug.Log($"成功连接服务端.");
//发布消息
Messenger.Publish("连接服务端", true);
//开始接收数据
socket.BeginReceive(readBuff.bytes, readBuff.writeIdx, readBuff.remain, 0, ReceiveCallback, socket);
}
catch (SocketException error)
{
Debug.Log($"连接服务端失败：{error}");
isConnecting = false;
//发布消息
Messenger.Publish("连接服务端", false);
}
}BeginReceive的回调函数ReceiveCallback会判断是否成功收到数据，如果收到数据长度为0，断开连接；如果收到正常的数据，更新缓冲区的writeIdx，再调用处理消息的函数OnReceiveData：
代码语言：javascript复制//Receive回调
private static void ReceiveCallback(IAsyncResult ar)
{
try
{
Socket socket = (Socket)(ar.AsyncState);
//获取接收数据长度
int count = socket.EndReceive(ar);
if (count == 0)
{
Close();
Debug.Log("关闭连接.");
return;
}
readBuff.writeIdx = count;
//处理二进制消息
OnReceiveData();
//继续接收数据
if (readBuff.remain < 8)
{
readBuff.MoveBytes();
readBuff.ReSize(readBuff.length * 2);
}
socket.BeginReceive(readBuff.bytes, readBuff.writeIdx, readBuff.remain, 0, ReceiveCallback, socket);
}
catch (SocketException error)
{
Debug.Log($"接收数据失败: {error}");
}
}处理数据：
OnReceiveData中进行协议的解码，并把协议对象添加到消息列表msgList，通信协议与服务端同样使用ProtoBuf，因此需要将protobuf-net.dll导入Unity工程中，并在代码中引入命名空间ProtoBuf，注意将它们在Init函数中进行初始化：
代码语言：javascript复制//消息列表
private static List<IExtensible> msgList;
//消息列表长度
private static int msgCount;
//数据处理
private static void OnReceiveData()
{
//消息长度
if (readBuff.length <= 2) return;
//获取消息体长度
int readIdx = readBuff.readIdx;
byte[] bytes = readBuff.bytes;
Int16 bodyLength = (Int16)((bytes[readIdx 1] << 8) | bytes[readIdx]);
if (readBuff.length < bodyLength 2) return;
readBuff.readIdx = 2;
//解析协议名
string protoName = ProtoUtility.DecodeName(readBuff.bytes, readBuff.readIdx, out int nameCount);
if (string.IsNullOrEmpty(protoName))
{
Debug.Log("协议名解码失败.");
return;
}
readBuff.readIdx = nameCount;
//解析协议体
int bodyCount = bodyLength - nameCount;
IExtensible proto = ProtoUtility.Decode(protoName, readBuff.bytes, readBuff.readIdx, bodyCount);
readBuff.readIdx = bodyCount;
readBuff.CheckAndMoveBytes();
//添加到消息队列
lock (msgList)
{
msgList.Add(proto);
}
msgCount ;
//继续读取消息
if (readBuff.length > 2)
{
OnReceiveData();
}
}
定义每帧处理协议的最大数量，并处理协议：
代码语言：javascript复制//每一次Update处理的消息量
private static readonly int MAX_MESSAGE_FIRE = 10;
//协议处理
private static void ProtoUpdate()
{
//初步判断 提升效率
if (msgCount == 0) return;
//重复处理消息
for (int i = 0; i < MAX_MESSAGE_FIRE; i )
{
//获取第一条消息
IExtensible msg = null;
lock (msgList)
{
if (msgList.Count > 0)
{
msg = msgList[0];
msgList.RemoveAt(0);
msgCount--;
}
}
//分发消息
if (msg != null)
{
Messenger.Publish(msg.GetType().Name, msg);
}
else
{
break;
}
}
}
public static void Update()
{
ProtoUpdate();
}
参考资料：《Unity3D网络游戏实战》（第2版）罗培羽 著
