TCP UDP基本编程（一）

2023-12-02 10:10:04

tcp udp均可以用来网络通信，在使用之前建议先搜索一下相关网络连接的基本知识，可以更好的理解和使用，tcp建议看下如下文章：https://blog.csdn.net/chuangsun/article/details/67640242，建议多搜一下多看看。

直接上正文。。。。。。。。。。。。。。。

（1）socket类

采用socket类，使用最基本的同步方法。

tcp服务端

using System;

using System.Net;

using System.Net.Sockets;

using System.Text;

using System.Threading;

namespace net

{

    class Program

    {

        static void Main(string[] args)

        {

            string host = "127.0.0.1";

            IPAddress ip = IPAddress.Parse(host);

            //定义侦听端口

            //IPEndPoint ipEnd = new IPEndPoint(IPAddress.Any, 8889);

            IPEndPoint ipEnd = new IPEndPoint(IPAddress.Any, );

            Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            socket.Bind(ipEnd);

            socket.Listen();

            Console.Write("Waiting for a client\r\n");

            //一旦接受连接，创建一个客户端

            Socket client = socket.Accept();

            IPEndPoint ipEndClient = (IPEndPoint)client.RemoteEndPoint;

            Console.Write("已连接:IP: {0}  端口: {1}\r\n", ipEndClient.Address, ipEndClient.Port);

            while(true)

            {

                //接收数据

                byte[] recv1 = new byte[];

                int count1 = client.Receive(recv1);

                string str = Encoding.ASCII.GetString(recv1, , count1);

                Console.WriteLine("Client:" + Encoding.ASCII.GetString(recv1, , count1));

                if(str=="exit")

                {

                    break;

                }

                //发送数据

                string welcome = "Server received:"+ str;

                byte[] data = new byte[];

                data = Encoding.ASCII.GetBytes(welcome);

                client.Send(data, data.Length, SocketFlags.None);

            }

            Thread.Sleep();

            Console.Write("\r\n断开连接： {0}", ipEndClient.Address);

            client.Close();

            socket.Close();

            Console.ReadKey();

        }

    }

}

tcp客户端

using System;

using System.Net;

using System.Net.Sockets;

using System.Collections.Generic;

using System.Text;

using System.Threading;

namespace client

{

    class Program

    {

        static void Main(string[] args)

        {

            //定义主机的IP及端口

            IPAddress ip = IPAddress.Parse("127.0.0.1");

            IPEndPoint ipEnd = new IPEndPoint(ip, );

            Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            socket.Connect(ipEnd);

            while(true)

            {

                //发送数据

                string msg = Console.ReadLine();

                byte[] msgBytes = new byte[];

                msgBytes = Encoding.ASCII.GetBytes(msg);

                socket.Send(msgBytes, msgBytes.Length, SocketFlags.None);

                //接收数据

                byte[] recvMsg = new byte[];

                int count = socket.Receive(recvMsg);

                string recvStr = Encoding.ASCII.GetString(recvMsg, , count);

                Console.WriteLine(recvStr);

                if(msg=="exit")

                {

                    break;

                }

            }

            Thread.Sleep();

            Console.Write("断开连接");

            socket.Shutdown(SocketShutdown.Both);

            socket.Close();

            Console.ReadKey();

        }

    }

}

udp服务端：

using System;

using System.Text;

using System.Net;

using System.Net.Sockets;

namespace UDP

{

    class Program

    {

        static void Main(string[] args)

        {

            int recv;

            byte[] data = new byte[];

            IPEndPoint ip = new IPEndPoint(IPAddress.Any, );

            Socket Server = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

            Server.Bind(ip);

            Console.WriteLine("Server ready!");

            //得到客户机IP

            //IPEndPoint sender = new IPEndPoint(IPAddress.Any, 0);

            //EndPoint Remote = (EndPoint)(sender);

            //recv = Server.ReceiveFrom(data, ref Remote);

            //Console.Write("Message from "+Remote.ToString()+":");

            //Console.WriteLine(Encoding.ASCII.GetString(data, 0, recv));

            ////客户机连接成功后，发送信息

            //string welcome = "Hello ! ";

            //data = Encoding.ASCII.GetBytes(welcome);

            //Server.SendTo(data, data.Length, SocketFlags.None, Remote);

            while(true)

            {

                //得到客户机IP

                IPEndPoint sender = new IPEndPoint(IPAddress.Any, );

                EndPoint Remote =sender;

                recv = Server.ReceiveFrom(data, ref Remote);

                string recvStr = Encoding.ASCII.GetString(data, , recv);

                Console.Write("Message from " + Remote.ToString() + ":");

                Console.WriteLine(recvStr);

                //客户机连接成功后，发送信息

                string welcome = "Server received: "+ recvStr;

                data = Encoding.ASCII.GetBytes(welcome);

                Server.SendTo(data, data.Length, SocketFlags.None, Remote);

            }

            //while (true)

            //{

            //    data = new byte[1024];

            //    //发送接收信息

            //    recv = Server.ReceiveFrom(data, ref Remote);

            //    Console.Write("Message from " + Remote.ToString() + ":");

            //    Console.WriteLine(Encoding.ASCII.GetString(data, 0, recv));

            //    if (Encoding.ASCII.GetString(data, 0, recv) == "exit")

            //        break;

            //    Server.SendTo(data, recv, SocketFlags.None, Remote);

            //}

            //Console.WriteLine("停止");

            Server.Close();

            Console.ReadKey();

        }

    }

}

udp客户端：

using System;

using System.Text;

using System.Net;

using System.Net.Sockets;

namespace UDPClient

{

    class Program

    {

        static void Main(string[] args)

        {

            byte[] data = new byte[];

            IPEndPoint ip = new IPEndPoint(IPAddress.Parse("192.168.8.15"), );

            Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

            Console.WriteLine("Client ready:");

            //string welcome = "Server hello!";

            //data = Encoding.ASCII.GetBytes(welcome);

            //server.SendTo(data, data.Length, SocketFlags.None, ip);

            //IPEndPoint sender = new IPEndPoint(IPAddress.Any, 0);

            //EndPoint Remote = (EndPoint)sender;

            //data = new byte[1024];

            //int recv = server.ReceiveFrom(data, ref Remote);

            //Console.Write("Message from "+Remote.ToString()+":");

            //Console.WriteLine(Encoding.ASCII.GetString(data, 0, recv));

            while(true)

            {

                string welcome = Console.ReadLine();

                data = Encoding.ASCII.GetBytes(welcome);

                server.SendTo(data, data.Length, SocketFlags.None, ip);

                IPEndPoint sender = new IPEndPoint(IPAddress.Any, );

                EndPoint Remote = sender;

                data = new byte[];

                int recv = server.ReceiveFrom(data, ref Remote);

                Console.Write("Message from " + Remote.ToString() + ":");

                Console.WriteLine(Encoding.ASCII.GetString(data, , recv));

            }

            //while (true)

            //{

            //    input = Console.ReadLine();

            //    server.SendTo(Encoding.ASCII.GetBytes(input), Remote);

            //    if (input == "exit")

            //        break;

            //    data = new byte[1024];

            //    recv = server.ReceiveFrom(data, ref Remote);

            //    stringData = Encoding.ASCII.GetString(data, 0, recv);

            //    Console.Write("Message from " + Remote.ToString() + ":");

            //    Console.WriteLine(stringData);

            //}

            Console.WriteLine("停止");

            server.Close();

            Console.ReadKey();

        }

    }

}

（2）TcpClient UdpClient TcpListener类

上述连个类为.NET自封装两个类。

tcp服务端：

using System;

using System.Net;

using System.Net.Sockets;

using System.Text;

namespace TcpServerT

{

    class Program

    {

        static void Main(string[] args)

        {

            //IPAddress IP = IPAddress.Parse("127.0.0.1");

            TcpListener listener = new TcpListener(IPAddress.Any, );

            listener.Start();

            Console.WriteLine("开始监听:");

            //此处也可以采用socket 接收，可以方便进行socket操作

            //Socket s = listener.AcceptSocket();

            TcpClient client = listener.AcceptTcpClient();//接受一个Client

            Console.WriteLine("已连接:");

            NetworkStream stream = client.GetStream();//获取网络流

            Console.WriteLine("获取连接流:");

            string receiveString = "";

            while (true)

            {

                byte[] buffer = new byte[client.ReceiveBufferSize];

                stream.Read(buffer, , buffer.Length);//读取网络流中的数据

                receiveString = Encoding.Default.GetString(buffer).Trim('\0');//转换成字符串

                //StreamReader sr = new StreamReader(stream);

                //receiveString = sr.ReadToEnd();

                string sendMsg = "Server received:" + receiveString;

                byte[] sendBytes = Encoding.Default.GetBytes(sendMsg);

                stream.Write(sendBytes, , sendBytes.Length);

                stream.Flush();

                Console.WriteLine(receiveString);

                //Console.WriteLine("While++");

                if (receiveString == "exit")

                {

                    stream.Close();//关闭流

                    client.Close();//关闭Client

                    break;

                }

            }

            listener.Stop();

        }

    }

}

tcp客户端：

using System;

using System.Net;

using System.Net.Sockets;

using System.Text;

namespace TcpClientT

{

    class Program

    {

        static void Main(string[] args)

        {

            //IPAddress IP = IPAddress.Parse("192.168.8.15");

            //IPEndPoint ip = new IPEndPoint(IP, 1234);

            //TcpClient client = new TcpClient("192.168.8.15",1234);

            IPEndPoint ip = new IPEndPoint(IPAddress.Any, );

            TcpClient client = new TcpClient("127.0.0.1", );

            NetworkStream sendStream = client.GetStream();

            while (true)

            {

                string msg = Console.ReadLine();

                Byte[] sendBytes = Encoding.Default.GetBytes(msg);

                sendStream.Write(sendBytes, , sendBytes.Length);

                sendStream.Flush();

                //StreamWriter sw = new StreamWriter(sendStream);

                //sw.WriteLine(msg);

                //sw.Flush();

                byte[] buffer = new byte[client.ReceiveBufferSize];

                sendStream.Read(buffer, , buffer.Length);//读取网络流中的数据

                string receiveMsg = Encoding.Default.GetString(buffer).Trim('\0');//转换成字符串  

                Console.WriteLine(receiveMsg);

                if (msg == "exit")

                {

                    sendStream.Close();//关闭网络流

                    break;

                }

            }

            client.Close();//关闭客户端

        }

    }

}

udp服务端

using System;

using System.Collections.Generic;

using System.Linq;

using System.Net;

using System.Net.Sockets;

using System.Text;

namespace UdpServer

{

    class Program

    {

        static void Main(string[] args)

        {

            UdpClient udpServer = new UdpClient();

            while (true)

            {

                var remoteEP = new IPEndPoint(IPAddress.Any, );

                byte[] recvData = udpServer.Receive(ref remoteEP); // listen on port 11000

                string recvString = Encoding.Default.GetString(recvData);

                Console.Write("Source from" + remoteEP.ToString()+":"+ recvString);

                if(recvString=="exit")

                {

                    break;

                }

                string sendString = "Server received:" + recvString;

                byte[] sendData = Encoding.Default.GetBytes(sendString);

                udpServer.Send(sendData, sendData.Length, remoteEP); // reply back

            }

            udpServer.Close();

        }

    }

}

udp客户端：

using System;

using System.Collections.Generic;

using System.Linq;

using System.Net;

using System.Net.Sockets;

using System.Text;

namespace UdpClientT

{

    class Program

    {

        static void Main(string[] args)

        {

            UdpClient client = new UdpClient();

            IPEndPoint ep = new IPEndPoint(IPAddress.Parse("127.0.0.1"), ); // endpoint where server is listening

            client.Connect(ep);

            while(true)

            {

                string sendString = Console.ReadLine();

                byte[] sendData = Encoding.Default.GetBytes(sendString);

                client.Send(sendData, sendData.Length);

                byte[] recvData = client.Receive(ref ep);

                string recvString = Encoding.Default.GetString(recvData);

                Console.WriteLine(recvString);

                if (sendString == "exit") break;

            }

            client.Close();

        }

    }

}

PS：最基本的同步方法为阻塞线程模式，即在接受消息或者服务端等待连接过程中，主程序在此位置属于阻塞（卡住）状态，只有这一步执行完毕（收到消息或者建立连接）才会进行下一步。所以可以通过死循环来实现循环接受消息。

udp不存在严格意义上的客户端服务端，只是要确定消息发送的目标主机

如            Socket client = socket.Accept();

int count1 = client.Receive(recv1);

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