.NET Socket通信入门实例

黑色简洁风格的 Socket 通信代码，适合刚上手.NET 网络开发的朋友。

Socket 通信的原理其实不难理解，就是让两台设备通过网络“说话”。在.NET 里用起来也挺顺的，Socket类功能全，关键是上手也不复杂。

服务器端的思路蛮清晰的：新建 Socket、绑定 IP 和端口、开启监听，等着客户端连进来。客户端也是类似套路，Connect()一下就能搭上线。

收发数据这块儿记住一句话就行：一切都是字节流。所以你发啥都得转成 byte 数组。来回用Send()和Receive()搞定，逻辑清爽，响应也快。

下面这段服务器代码挺经典的，逻辑清晰，不多不少刚刚好：

Socket serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint ipEndPoint = new IPEndPoint(IPAddress.Any, 12345);
serverSocket.Bind(ipEndPoint);
serverSocket.Listen(10);
while (true)
{
  Socket clientSocket = serverSocket.Accept();
  byte[] buffer = new byte[1024];
  int received = clientSocket.Receive(buffer);
  string data = Encoding.ASCII.GetString(buffer, 0, received);
  Console.WriteLine("Received: " + data);
  string response = "Hello, Client!";
  clientSocket.Send(Encoding.ASCII.GetBytes(response));
}

客户端代码也一样利索：

Socket clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPAddress serverIP = IPAddress.Parse("127.0.0.1");
IPEndPoint serverEndPoint = new IPEndPoint(serverIP, 12345);
clientSocket.Connect(serverEndPoint);
string message = "Hello, Server!";
byte[] data = Encoding.ASCII.GetBytes(message);
clientSocket.Send(data);
byte[] buffer = new byte[1024];
int received = clientSocket.Receive(buffer);
string response = Encoding.ASCII.GetString(buffer, 0, received);
Console.WriteLine("Received: " + response);

如果你想试着跑一跑，不妨找找名为SocketDemo的源码包，通常里面都有完整项目，跑起来一目了然。嗯，对了，别忘了异常和关闭 Socket，别让程序卡住了。