C# Socket 编程 Sample

使用Socket通信的服务器端编程，熟悉了服务器端和客户端的通信流程，实现了收发信息、文件传送以及震动功能

服务器端先创建Socket，然后将其和本地ip地址以及端口号连接，也就是使用Bind方法，然后使用Listen方法监听。

用Accept方法接受客户端的连接申请，并且等待客户端连接（在winform中，由于Accept方法是阻塞方法，必须创建一个线程来执行，防止主窗体卡死）

客户端连接成功Accept方法会返回一个用于发送和接收消息的Socket，之后就要用这个socket进行通信

在通信过程中要像实现不同功能，比如传送文件，就要在发送的字节流中使用一定的位置来存储信息，也就是使用自己的协议，在这个案例中，取第一个字节标识信息，0代表发送信息，1代表传递文件，2代表震动窗体

服务端代码如下

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Net.Sockets;
using System.Net;
using System.Threading;
using System.IO;
 
namespace ServerReview
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        private Socket socketSend;
        private Socket socketWatch;
        private Dictionary<string, Socket> socketClientList = new Dictionary<string, Socket>();
        private void btnStart_Click(object sender, EventArgs e)
        {
            socketWatch = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            IPAddress ip = IPAddress.Any;
            IPEndPoint iep = new IPEndPoint(ip, Convert.ToInt32(txtPort.Text));
            //将套接字和本机地址绑定
            socketWatch.Bind(iep);
            ShowMsg("监听成功");
            //用Listen监听
            socketWatch.Listen(10);
            //创建新线程不停接受客户端请求
            Thread thread = new Thread(ServerAccept);
            thread.IsBackground = true;
            thread.Start();
        }
        private void ServerAccept()
        {
            while (true)
            {
                socketSend = socketWatch.Accept();
                socketClientList.Add(socketSend.RemoteEndPoint.ToString(), socketSend);
                cboUsers.Items.Add(socketSend.RemoteEndPoint.ToString());
                ShowMsg(socketSend.RemoteEndPoint.ToString() + "连接成功");
                //开启新线程不停接收消息
                Thread thread = new Thread(ServerReceive);
                thread.IsBackground = true;
                thread.Start();
            }
        }
        private void ServerReceive()
        {
            while (true)
            {
                try
                {
                    byte[] buffer = new byte[1024 * 1024 * 2];
                    int byteNum = socketSend.Receive(buffer);
                    if (byteNum == 0)
                    {
                        break;
                    }
                    string str = Encoding.UTF8.GetString(buffer, 0, byteNum);
                    ShowMsg(socketSend.RemoteEndPoint.ToString() + ":" + str);
                }
                catch { }
            }
        }
        private void ShowMsg(string str)
        {
            txtLog.AppendText(str + "\r\n");
        }
 
        private void Form1_Load(object sender, EventArgs e)
        {
            Control.CheckForIllegalCrossThreadCalls = false;
        }
 
        private void btnSend_Click(object sender, EventArgs e)
        {
            string str = txtMsg.Text;
            List<byte> list = new List<byte>();
            list.Add(0);
            byte[] buffer = Encoding.UTF8.GetBytes(str);
            list.AddRange(buffer);
            byte[] newBuffer = list.ToArray();
            string ip = cboUsers.SelectedItem.ToString();
            socketClientList[ip].Send(newBuffer);
        }
 
        private void btnSelectFile_Click(object sender, EventArgs e)
        {
            OpenFileDialog ofd = new OpenFileDialog();
            ofd.InitialDirectory = @"D:\";
            ofd.Title = "请选择要发送的文件";
            ofd.Filter = "所有文件|*.*";
            ofd.ShowDialog();
            txtFilePath.Text = ofd.FileName;
        }
 
        private void btnSendFile_Click(object sender, EventArgs e)
        {
            string path = txtFilePath.Text;
            using(FileStream fsRead = new FileStream(path, FileMode.Open, FileAccess.Read))
            {
                try
                {
                    byte[] buffer = new byte[1024 * 1024 * 5];
                    int l = fsRead.Read(buffer, 0, buffer.Length);
                    List<byte> list = new List<byte>();
                    list.Add(1);
                    list.AddRange(buffer);
                    byte[] newBuffer = list.ToArray();
                    socketClientList[cboUsers.SelectedItem.ToString()].Send(newBuffer,0,l+1,SocketFlags.None);
                }
                catch { }
            }
        }
 
        private void btnShake_Click(object sender, EventArgs e)
        {
            byte[] buffer = new byte[1];
            buffer[0] = 2;
            socketClientList[cboUsers.SelectedItem.ToString()].Send(buffer);
        }
    }
}

客户端代码如下：

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.Threading.Tasks;
using System.Windows.Forms;
 
namespace ClientRevier
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
 
        private void Form1_Load(object sender, EventArgs e)
        {
            Control.CheckForIllegalCrossThreadCalls = false;
        }
        private Socket socketClient;
        private void btnStart_Click(object sender, EventArgs e)
        {
            socketClient = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            IPAddress ip = IPAddress.Parse(txtServer.Text);
            IPEndPoint iep = new IPEndPoint(ip, Convert.ToInt32(txtPort.Text));
            socketClient.Connect(iep);
            ShowMsg("连接成功");
            //因为要不停接受消息，所以用while循环，并且为了接受消息的同时能做其他事，把这个放到线程中执行
            Thread thread = new Thread(ClientRecieve);
            thread.IsBackground = true;
            thread.Start();
        }
        private void ClientRecieve()
        {
            while (true)
            {
                byte[] buffer = new byte[1024 * 1024 * 2];
                int byteNum = socketClient.Receive(buffer);
                if (byteNum == 0)
                {
                    break;
                }
                switch (buffer[0])
                {
                    case 0:
                        string str = Encoding.UTF8.GetString(buffer, 1, byteNum-1);
                        ShowMsg(socketClient.RemoteEndPoint + ":" + str);
                        break;
                    case 1:
                        SaveFileDialog sfd = new SaveFileDialog();
                        sfd.InitialDirectory = @"D\";
                        sfd.Title = "请选择需要保存的路径";
                        sfd.Filter = "文本文件|*.txt|图片文件|*.jpg|所有文件|*.*";
                        sfd.ShowDialog(this);
                        using(FileStream fsWrite = new FileStream(sfd.FileName, FileMode.OpenOrCreate, FileAccess.Write))
                        {
                            fsWrite.Write(buffer, 1, byteNum - 1);
                            MessageBox.Show("保存成功");
                        }
                        break;
                    case 2:
                        for(int i = 0; i < 1000; i++)
                        {
                            this.Location = new Point(200, 200);
                            this.Location = new Point(230, 230);
                        }
                        break;
                    default:break;
                }
                
            }
        }
        private void ShowMsg(string str)
        {
            txtLog.AppendText(str + "\r\n");
        }
 
        private void btnSend_Click(object sender, EventArgs e)
        {
            string str = txtMsg.Text;
            byte[] buffer = Encoding.UTF8.GetBytes(str);
            socketClient.Send(buffer);
 
        }
    }
}