1 前言
同步 Socket 通讯 中的 Accept、Connect、Receive 等方法会阻塞当前线程，当前线程必须等待这些方法执行完，才会继续往下执行，用户需要另开线程执行这些耗时方法，否则会阻塞主线程，导致 UI 卡顿。
异步 Socket 通讯中，通过 BeginAccept、EndAccept、BeginConnect、EndConnect、BeginReceive、EndReceive 等方法实现请求、连接、收消息等效果，这些方法通过回调（Callback）的方式实现异步通讯，并且不会阻塞主线程。
在 BeginXXX（BeginAccept、BeginConnect、BeginReceive）方法的入参里，需要传递一个 Callback，当方法响应时（如收到请求、已连接上服务、收到消息），就会执行 Callback 里的内容，Callback 里通过 EndXXX（EndAccept、EndConnect、EndReceive）方法拿到响应信息，并进行相关数据处理。为避免在回调执行结束后程序也结束，从而不能继续收发消息，需要在回调的最后一行通过递归的方式执行 BeginXXX 方法，从而保证程序一直循环下去。
2 案例
1）Socket 基本操作基类
BaseSocket.cs
using System;
public abstract class BaseSocket {
public virtual void OnAccept(IAsyncResult ar) {} // 服务端接收到连接的回调函数
public virtual void OnConnect(IAsyncResult ar) {} // 客户端连接上服务端的回调函数
public abstract void OnReceive(IAsyncResult ar); // 接收到消息的回调函数
public abstract void Send(string msg); // 发送消息
}
2）服务端
AsyncSocketServer.cs
using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
public class AsyncSocketServer : BaseSocket {
private Socket serverSocket; // 服务端通讯主机socket, 监听打进来的电话，并转接给客服
private Socket kefuScoket; // 客服socket, 负责与客户一对一通讯
private Action<string> msgCallback; // 消息回调
private byte[] readBuff; // 收到消息的缓存
public AsyncSocketServer(Action<string> callback) {
msgCallback = callback;
serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint endPoint = new IPEndPoint(IPAddress.Any, 12345);
serverSocket.Bind(endPoint); // 绑定ip和端口
serverSocket.Listen(1); // 监听电话连接, 设置最大客服人数, 如果是0就是无限个客服
serverSocket.BeginAccept(OnAccept, serverSocket); // 接电话, 分配客服和客户进行一对一通信, 收到电话就会回调OnAccept方法
}
public override void OnAccept(IAsyncResult ar) { // 有客户连接上时, 回调此方法
kefuScoket = serverSocket.EndAccept(ar);
msgCallback("客服的本地端口是: " + kefuScoket.LocalEndPoint.ToString());
msgCallback("客户的远程端口是: " + kefuScoket.RemoteEndPoint.ToString());
readBuff = new byte[1024];
BeginReceive();
serverSocket.BeginAccept(OnAccept, serverSocket);
}
public override void OnReceive(IAsyncResult ar) { // 收到消息时, 回调此方法
int count = serverSocket.EndReceive(ar);
string msg = Encoding.UTF8.GetString(readBuff, 0, count);
msgCallback("客户发来消息: " + msg);
Array.Clear(readBuff, 0, readBuff.Length); // 清空缓存
BeginReceive();
}
public override void Send(string msg) {
byte[] buffer = Encoding.UTF8.GetBytes(msg);
kefuScoket.Send(buffer);
}
private void BeginReceive() {
kefuScoket.BeginReceive(
readBuff, // 消息缓存
0, readBuff.Length, // 消息接收的起始点以及长度
SocketFlags.None, // 标志
OnReceive, // 接收到消息的回调
serverSocket // 状态
);
}
~AsyncSocketServer() {
kefuScoket.Close();
serverSocket.Close();
}
}
3）客户端
AsyncSocketClient.cs
using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
public class AsyncSocketClient : BaseSocket {
private Socket clientSocket; // 客户端socket
private Action<string> msgCallback; // 消息回调
private byte[] readBuff; // 收到消息的缓存
public AsyncSocketClient(Action<string> callback) {
msgCallback = callback;
clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint endPoint = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 12345);
clientSocket.BeginConnect(endPoint, OnConnect, clientSocket); // 连接服务器
}
public override void OnConnect(IAsyncResult ar) { // 连上服务器时, 回调此方法
clientSocket.EndConnect(ar);
readBuff = new byte[1024];
BeginReceive();
}
public override void OnReceive(IAsyncResult ar) { // 收到消息时, 回调此方法
Socket workingSocket = ar.AsyncState as Socket;
int count = workingSocket.EndReceive(ar);
string msg = Encoding.UTF8.GetString(readBuff, 0, count);
msgCallback("客服发来消息: " + msg);
Array.Clear(readBuff, 0, readBuff.Length); // 清空缓存
BeginReceive();
}
public override void Send(string msg) {
byte[] buffer = Encoding.UTF8.GetBytes(msg);
clientSocket.Send(buffer);
}
private void BeginReceive() {
clientSocket.BeginReceive(
readBuff, // 消息缓存
0, readBuff.Length, // 消息接收的起始点以及长度
SocketFlags.None, // 标志
OnReceive, // 接收到消息的回调
clientSocket // 状态
);
}
~AsyncSocketClient() {
clientSocket.Close();
}
}
4）测试类
AsyncSocketTest.cs
using UnityEngine;
public class AsyncSocketTest : MonoBehaviour {
private BaseSocket socket; // 客户端/服务端socket
private string sendText; // 发送的消息
private string receiveText; // 接收的消息
private bool isSideInited = false; // 是否已初始化端测
private string sideTag = null; // 端测标记, 服务端/客户端
private void Awake() {
Application.runInBackground = true; // 支持后台运行
}
private void OnGUI() {
InitSide();
initSideView();
}
private void InitSide() { // 初始化端测
if (!isSideInited) {
CreateServer();
CreateClient();
}
}
private void CreateServer() { // 创建服务器
if (GUILayout.Button("创建服务器")) {
socket = new AsyncSocketServer((msg) => {
receiveText += msg + "\n";
});
sideTag = "服务端";
isSideInited = true;
}
}
private void CreateClient() { // 创建客户端
if (GUILayout.Button("创建客户端")) {
socket = new AsyncSocketClient((msg) => {
receiveText += msg + "\n";
});
sideTag = "客户端";
isSideInited = true;
}
}
private void initSideView() { // 初始化端测界面
if (isSideInited) {
GUILayout.Label(sideTag);
sendText = GUILayout.TextField(sendText);
if (GUILayout.Button("发送")) {
socket.Send(sendText);
}
GUILayout.Label("接收到的消息: ");
GUILayout.Label(receiveText);
}
}
}
5）运行效果
声明：本文转自【Unity3D】异步Socket通讯
网友评论