C#基于TCP通信协议的实现示例

new TcpClient(server, port)

AcceptTcpClient()

stream.Close()

client.Close()

using System;
using System.Net.Sockets;
using System.Text;
​
namespace TCpClient
{
    internal class Program
    {
        static void Main(string[] args)
        {
            // 定义服务器的IP地址和端口号
            string serverIp = "172.16.0.14"; // 替换为实际服务器IP（本机测试可填127.0.0.1）
            int serverPort = 9898;
​
            TcpClient tcpClient = null;
            NetworkStream networkStream = null;
​
            try
            {
                // 1. 建立TCP连接（底层三次握手）
                tcpClient = new TcpClient(serverIp, serverPort);
                Console.WriteLine($"成功连接到服务器 {serverIp}:{serverPort}");
​
                // 2. 获取网络流（用于数据收发）
                networkStream = tcpClient.GetStream();
​
                // 3. 发送数据到服务器
                Console.WriteLine("请输入要发送的消息：");
                string sendMessage = Console.ReadLine();
                byte[] sendData = Encoding.UTF8.GetBytes(sendMessage);
                networkStream.Write(sendData, 0, sendData.Length);
                Console.WriteLine($"客户端已发送：{sendMessage}");
​
                // 4. 接收服务器响应
                byte[] receiveBuffer = new byte[256]; // 定义缓冲区存储接收的数据
                int receiveBytes = networkStream.Read(receiveBuffer, 0, receiveBuffer.Length);
                string receiveMessage = Encoding.UTF8.GetString(receiveBuffer, 0, receiveBytes);
                Console.WriteLine($"客户端收到服务器响应：{receiveMessage}");
            }
            catch (Exception ex)
            {
                Console.WriteLine($"连接/通信异常：{ex.Message}");
            }
            finally
            {
                // 5. 释放资源（底层四次挥手）
                if (networkStream != null) networkStream.Close();
                if (tcpClient != null) tcpClient.Close();
            }
​
            Console.WriteLine("客户端程序结束，按任意键退出...");
            Console.ReadKey();
        }
    }
}

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
​
namespace TCPServer
{
    internal class Program
    {
        static void Main(string[] args)
        {
            // 定义监听端口
            int listenPort = 9898;
            TcpListener tcpListener = null;
            TcpClient client = null;
            NetworkStream networkStream = null;
​
            try
            {
                // 1. 初始化监听器并启动监听
                tcpListener = new TcpListener(IPAddress.Any, listenPort);
                tcpListener.Start();
                Console.WriteLine($"服务器已启动，正在监听端口 {listenPort}...");
​
                // 2. 循环等待客户端连接（单线程，仅处理一个客户端）
                while (true)
                {
                    // 阻塞等待客户端连接
                    client = tcpListener.AcceptTcpClient();
                    Console.WriteLine("有客户端成功连接！");
​
                    // 3. 获取网络流，处理数据交互
                    networkStream = client.GetStream();
                    byte[] receiveBuffer = new byte[256];
                    int readBytes;
​
                    // 循环读取客户端发送的数据（直到客户端断开）
                    while ((readBytes = networkStream.Read(receiveBuffer, 0, receiveBuffer.Length)) != 0)
                    {
                        // 解析接收的字节数据为字符串
                        string receiveMessage = Encoding.UTF8.GetString(receiveBuffer, 0, readBytes);
                        Console.WriteLine($"服务器收到客户端数据：{receiveMessage}");
​
                        // 4. 向客户端发送响应
                        string responseMessage = "已收到客户端消息";
                        byte[] responseData = Encoding.UTF8.GetBytes(responseMessage);
                        networkStream.Write(responseData, 0, responseData.Length);
                        Console.WriteLine($"服务器已发送响应：{responseMessage}");
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine($"服务器异常：{ex.ToString()}");
            }
            finally
            {
                // 5. 释放资源
                if (networkStream != null) networkStream.Close();
                if (client != null) client.Close();
                if (tcpListener != null) tcpListener.Stop();
            }
​
            Console.WriteLine("服务器程序结束，按任意键退出...");
            Console.ReadKey();
        }
    }
}