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(10);
                //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[1024 * 1024];
                    //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 == 0)
                    {
                        break;
                    }
                    string str = Encoding.UTF8.GetString(buffer, 0, num);
                    ShowMessage($"{socketSend.RemoteEndPoint}：{str}");
                }
                catch (Exception)
                {
                }
            }
        }
        private void ShowMessage(string str)
        {
            this.textListen.AppendText($"{str}
");
        }

        /// <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(0);
                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[1024 * 1024 * 20];
                    int length = fs.Read(by, 0, by.Length);
                    //给发送的内容添加前缀，如果加1，则表示发文件
                    list.Add(1);
                    list.AddRange(by);
                    byte[] newBy = list.ToArray();
                    dic[dropList.SelectedItem.ToString().Trim()].Send(newBy, 0, length + 1, 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:UsersAdministratorDesktop";
            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[1024 * 1024 * 10]; //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 == 0)
                    {
                        break;
                    }
                    //如果为0接收消息
                    if (buffer[0]==0)
                    {
                        //去掉前缀
                        string str = Encoding.UTF8.GetString(buffer, 1, length-1);
                        ShowMess(socketSend.RemoteEndPoint + "：" + str);
                    }
                    //如果为1接收文件
                    else if (buffer[0]==1)
                    {
                        //保存文件
                        SaveFileDialog sfd = new SaveFileDialog();
                        sfd.InitialDirectory = @"C:UsersAdministratorDesktop";
                        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, 1, length - 1);
                        }
                        MessageBox.Show("保存成功");
                    } 
                }
                catch (Exception)
                { 
                }
            }
        }
        private void ShowMess(string str)
        {
            this.clientMess.AppendText($"{str}
");
        }

        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);
        }
    }
}