Socket网络编程(winform)

【服务器】

 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Data;
 using System.Drawing;
 using System.IO;
 using System.Linq;
 using System.Net;
 using System.Net.Sockets;
 using System.Text;
 using System.Threading;
 using System.Windows.Forms;

 namespace SocketDemo
 {
     public partial class Server : Form
     {
         private Socket socketSend;

         public Server()
         {
             InitializeComponent();

         }
         private void Form1_Load(object sender, EventArgs e)
         {
             Control.CheckForIllegalCrossThreadCalls = false;
             this.filePath.ReadOnly = true;
         }

         private void button1_Click(object sender, EventArgs e)
         {
             try
             {
                 //当点击开始监听时，在服务器端创建一个负责监听的ip地址和端口号
                 Socket socketWatch = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
                 IPAddress ip = IPAddress.Any;
                 //创建一个端口号
                 IPEndPoint point = new IPEndPoint(ip, Convert.ToInt32(this.portNum.Text));
                 //创建监听
                 socketWatch.Bind(point);
                 ShowMessage("监听成功！");
                 socketWatch.Listen();
                 //等待客户端的链接，并且创建一个负责通信的socket
                 Thread thread = new Thread(Listen);
                 thread.IsBackground = true;
                 thread.Start(socketWatch);
             }
             catch (Exception)
             {
             }
         }

         Dictionary<string, Socket> dic = new Dictionary<string, Socket>();

         /// <summary>
         /// 等待客户端链接，创建与之通信的scoket
         /// </summary>
         private void Listen(object o)
         {
             Socket socketWatch = o as Socket;
             while (true)
             {
                 try
                 {
                     //等待客户端的连接
                     socketSend = socketWatch.Accept();
                     //将连接过来的客户端存储至Dictionary和下拉框中，以便区分是哪个客户端
                     dic.Add(socketSend.RemoteEndPoint.ToString(), socketSend);
                     //将ip和端口号存入下拉框中
                     dropList.Items.Add(socketSend.RemoteEndPoint.ToString());
                     ShowMessage($"{socketSend.RemoteEndPoint.ToString()}:连接成功！");
                     //另外再开一个线程不停地接收客户端发来的消息
                     Thread thread = new Thread(Receive);
                     thread.IsBackground = true;
                     thread.Start(socketSend);
                 }
                 catch (Exception)
                 {
                 }
             }
         }

         /// <summary>
         /// 服务器不停地接收客户端发来的消息
         /// </summary>
         /// <param name="obj"></param>
         private void Receive(object obj)
         {
             Socket socketSend = obj as Socket;
             while (true)
             {
                 try
                 {
                     //服务器应该接收客户端发来的消息
                     byte[] buffer = new byte[ * ];
                     //实际接收的有效字节数
                     int num = socketSend.Receive(buffer);
                     //判断接收的字节是否为0，如果为0，则表明客户端已经下线
                     if (num == )
                     {
                         break;
                     }
                     string str = Encoding.UTF8.GetString(buffer, , num);
                     ShowMessage($"{socketSend.RemoteEndPoint}：{str}");
                 }
                 catch (Exception)
                 {
                 }
             }
         }
         private void ShowMessage(string str)
         {
             this.textListen.AppendText($"{str}\r\n");
         }

         /// <summary>
         /// 服务器发送消息给客户端
         /// </summary>
         /// <param name="sender"></param>
         /// <param name="e"></param>
         private void button2_Click(object sender, EventArgs e)
         {
             if (dropList.Text == "---请选择---")
             {
                 MessageBox.Show("请先选择您要发送的客户端");
                 return;
             }
             if (this.serverMsg.Text.Trim() == "" && this.filePath.Text.Trim() == "")
             {
                 MessageBox.Show("请输入信息或选择文件");
                 return;
             }
             List<byte> list = new List<byte>();

             if (this.serverMsg.Text.Trim() != "" && this.filePath.Text.Trim() == "")
             {
                 byte[] buffer = Encoding.UTF8.GetBytes(this.serverMsg.Text.Trim());
                 //给发送的内容添加前缀，如果加0，则表示发消息
                 list.Add();
                 list.AddRange(buffer);
                 byte[] newBuffer = list.ToArray();
                 dic[dropList.SelectedItem.ToString().Trim()].Send(newBuffer);
             }
             else if (this.filePath.Text.Trim() != "" && this.serverMsg.Text.Trim() == "")
             {
                 using (FileStream fs = new FileStream(filePath.Text.Trim(), FileMode.Open, FileAccess.Read))
                 {
                     byte[] by = new byte[ *  * ];
                     int length = fs.Read(by, , by.Length);
                     //给发送的内容添加前缀，如果加1，则表示发文件
                     list.Add();
                     list.AddRange(by);
                     byte[] newBy = list.ToArray();
                     dic[dropList.SelectedItem.ToString().Trim()].Send(newBy, , length + , SocketFlags.None);
                 }
             }
             else
             {
                 MessageBox.Show("只能是发送消息或传输文件中的一项");
             }
         }

         /// <summary>
         /// 打开所需的文件
         /// </summary>
         /// <param name="sender"></param>
         /// <param name="e"></param>
         private void openFile_Click(object sender, EventArgs e)
         {
             OpenFileDialog ofd = new OpenFileDialog();
             ofd.InitialDirectory = @"C:\Users\Administrator\Desktop";
             ofd.Title = "打开文件";
             ofd.Filter = "所有文件|*.*";
             ofd.ShowDialog();
             this.filePath.Text = ofd.FileName;
         }
     }
 }

【客户端】

 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Data;
 using System.Drawing;
 using System.IO;
 using System.Linq;
 using System.Net;
 using System.Net.Sockets;
 using System.Text;
 using System.Threading;
 using System.Windows.Forms;

 namespace 客户端
 {
     public partial class Client : Form
     {
         public Client()
         {
             InitializeComponent();
         }

         private void Form1_Load(object sender, EventArgs e)
         {
             Control.CheckForIllegalCrossThreadCalls = false;
         }

         Socket socketSend;
         private void button1_Click(object sender, EventArgs e)
         {
             try
             {
                 //创建一个负责通信的socket
                 socketSend = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
                 IPAddress ip = IPAddress.Parse(this.IpMess.Text.Trim());
                 IPEndPoint point = new IPEndPoint(ip, Convert.ToInt32(this.clientPort.Text.Trim()));
                 socketSend.Connect(point);
                 ShowMess("连接成功!");
                 //创建线程接收消息
                 Thread th = new Thread(Receive);
                 th.IsBackground = true;
                 th.Start();
             }
             catch (Exception)
             {
                 MessageBox.Show("可能是因为没有启动服务器监听！");
             }
         }
         private void Receive()
         {
             while (true)
             {
                 try
                 {
                     byte[] buffer = new byte[ *  * ]; //最长10M
                     //通过字节二进制来接收消息,获取字节长度
                     int length = socketSend.Receive(buffer);
                     if (length == )
                     {
                         break;
                     }
                     //如果为0接收消息
                     if (buffer[]==)
                     {
                         //去掉前缀
                         string str = Encoding.UTF8.GetString(buffer, , length-);
                         ShowMess(socketSend.RemoteEndPoint + "：" + str);
                     }
                     //如果为1接收文件
                     else if (buffer[]==)
                     {
                         //保存文件
                         SaveFileDialog sfd = new SaveFileDialog();
                         sfd.InitialDirectory = @"C:\Users\Administrator\Desktop";
                         sfd.Title = "选择文件";
                         sfd.Filter = "所有文件|*.*";
                         //弹出对话窗
                         sfd.ShowDialog(this);
                         using (var fs=new FileStream(sfd.FileName,FileMode.OpenOrCreate,FileAccess.Write))
                         {
                             fs.Write(buffer, , length - );
                         }
                         MessageBox.Show("保存成功");
                     }
                 }
                 catch (Exception)
                 {
                 }
             }
         }
         private void ShowMess(string str)
         {
             this.clientMess.AppendText($"{str}\r\n");
         }

         private void clientMess_TextChanged(object sender, EventArgs e)
         {

         }

         /// <summary>
         /// 客户端给服务器发送消息
         /// </summary>
         /// <param name="sender"></param>
         /// <param name="e"></param>
         private void sendBtn_Click(object sender, EventArgs e)
         {
             byte[] buffer = Encoding.UTF8.GetBytes(this.sendMsg.Text.Trim());
             socketSend.Send(buffer);
         }
     }
 }