C# Socket TCP 编程,客户端与服务端连接,发送字符串,文件

做了个winform的Socket服务端和客户端,能实现发送消息&文字

目前客户端还有几个bug(一些异常没处理好).客户端在接受一个文件之后才能正常接受文字消息,找了很久也不知道怎么改

以下是图片和一些关键点,最后是代码,注释不多,请多多指教

这部分是服务端

服务端创建一个socket对象

第一个参数 :寻址方案,ip版本4 第二个参数:套接字类型,字节流 第三个参数:协议,TCP

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

这时候可以在外边创建new一个空的socket对象比如serverSocket.来保存上面创建的对象,这样其他地方就能使用这个socket

例外,在外部创建一个List<Socket> list 来保存连客户端socket对象.后面要用

socket需要ip地址和port,注意参数转换类型

socket.Bind(new IPEndPoint(IPAddress.Parse(txtIP.Text.ToString()), int.Parse(txtPort.Text)));

设置连接等待队列的数量

socket.Listen(10);

开始服务,等待客户端连接,这时候需要开另外一个线程 来做这些事情,AcceptClientConnect是自己写的一个方法,将socket传给它

ThreadPool.QueueUserWorkItem(new WaitCallback(this.AcceptClientConnect), socket);

下面是AcceptClientConnect的代码, 当有客户端连接时,创建一个Socket对象.变量名为proxSocket,并且保存到list中,方便以后使用,另外,需要在创建一个线程来处理该客户端socket发送过来的数据.

public void AcceptClientConnect(object socket)        {            var serverSocket = socket as Socket;            this.AppendTextToTxtLog("服务器端开始接受客户端的链接");            while (true)            {                try                {                    var proxSocket = serverSocket.Accept();                    this.AppendTextToTxtLog(string.Format("客户端{0}连接上了", proxSocket.RemoteEndPoint.ToString()));                    ClientProxClentList.Add(proxSocket);                    //接受消息                    ThreadPool.QueueUserWorkItem(new WaitCallback(this.ReceiveData), proxSocket);                }                catch (Exception)                {                }                            }        }

其中AppendTextToTxtLog方法是给主窗口中传递文本信息,因为txtLog这个控件不是监听服务端连接的线程创建的.所以要用异步来让它把新消息复制到txtLog中,代码中if来判断是否是txtLog当前线程的控件

 public void AppendTextToTxtLog(string txt)        {            if (txtLog.InvokeRequired)            {                txtLog.BeginInvoke(new Action<string>(s =>                {                    this.txtLog.Text = string.Format("{0}\r\n{1}", s, txtLog.Text);                }), txt);            }            else            {                this.txtLog.Text = string.Format("{0}\r\n{1}", txt, txtLog.Text);            }        }

下面是处理客户端发送过来的数据的代码,new一个byte[]数组,变量名为data,代销为1024*1024,用来保存客户端发来的数据. int  readlen是实际接收到的数据的长度(data中没用的到部分会自动为null),服务端和客户端通信的时候,数据长度是大于0的.当数据长度等于0 的时候,说明客户端要断开连接,代码中有这个判断,还有try,catch捕获异常(这里处理的不怎么好),最后.当复合条件.发送过来的数据转换成字符串,这里用到了有效长度,截取,转换为字符串,添加到消息文本框中.

 public void ReceiveData(object obj)        {            Socket proxSocket = obj as Socket;            byte[] data = new byte[1024 * 1024];            while (true)            {                int readLen = 0;                try                {                    readLen = proxSocket.Receive(data, 0, data.Length, SocketFlags.None);                }                catch (Exception ex)                {                    //异常退出时                    AppendTextToTxtLog(string.Format("客户端{0}非正常退出", proxSocket.RemoteEndPoint.ToString()));                    ClientProxClentList.Remove(proxSocket);                    StopConnetct(proxSocket);                    return;                }                if (readLen<=0)                {                    //客户端正常退出                    AppendTextToTxtLog(string.Format("客户端:{0}正常退出", proxSocket.RemoteEndPoint.ToString()));                    ClientProxClentList.Remove(proxSocket);                    StopConnetct(proxSocket);                    return;//方法结束->终结当前接受客户端数据的异步线程                }                string txt = Encoding.Default.GetString(data, 0, readLen);                AppendTextToTxtLog(string.Format("接收到客户端{0}的消息{1}",proxSocket.RemoteEndPoint.ToString(),txt));            }        }

一下是发送消息的代码 ,这个客户端能发送字符串,文件和窗口晃动,在原本发送的byte[] data前面在增加一位,为1 的时候是发送字符串,2发送晃动.3发送文件,data数组前面加一位,new用一个新数组result,长度是data.length+1,之后用到了Buffer.BlockCopy()方法,参数分别是(原数组,原数组的开始位置,目标数组,目标数组的开始位置,原数组中取多长数据)

发送数据,客户端对象.Send(要发送的byte数组,开始位置,长度,发送接收行为),一般发送接收行为用SocketFlags.None就可以了.发送的时候遍历一下list中的客户端对象.判断一下是否连接.

 private void btnSend_Click(object sender, EventArgs e)        {            foreach (var proxSocket in ClientProxClentList)            {                if (proxSocket.Connected)                {                    //原始的字符串转换成的字节数组                    byte[] data = Encoding.Default.GetBytes(txtSendMsg.Text);                    //在头部加上标记字节                    byte[] result = new byte[data.Length + 1];                    //头部协议字节 1:代表字符串                    result[0] = 1;                    Buffer.BlockCopy(data, 0, result, 1, data.Length);                    proxSocket.Send(result, 0, result.Length,SocketFlags.None);                }            }        }

发送文件的方法,new一个新的byte数组,第一位设置为3,然后读取文件,转换为byte[]data,还是用Buffer.BlockCopy(),整合到变量名为result的byte数组中,遍历list中的客户端对象,如果是连接的,那么发送

private void button2_Click(object sender, EventArgs e)        {            using (OpenFileDialog ofd =new OpenFileDialog())            {                if (ofd.ShowDialog()!=DialogResult.OK)                {                    return;                }                byte[] data = File.ReadAllBytes(ofd.FileName);                byte[] result = new byte[data.Length + 1];                result[0] = 3;                Buffer.BlockCopy(data, 0, result, 1,data.Length);                foreach (var proxSocket in ClientProxClentList)                {                    if (!proxSocket.Connected)                    {                        continue;                    }                    proxSocket.Send(result, SocketFlags.None);                }            }                   }

最后一个是晃动的,只要发一个第一位是2的byte数组过去就好

 private void button1_Click(object sender, EventArgs e)        {            foreach (var proxSocket in ClientProxClentList)            {                if (proxSocket.Connected)                {                    proxSocket.Send(new byte[] { 2 }, SocketFlags.None);                }            }        }

下面是服务端的整体代码

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 ChatDemo{    public partial class Mainfrm : Form    {        public Mainfrm()        {            InitializeComponent();        }        private Socket serverSocket;        List<Socket> ClientProxClentList = new List<Socket>();        private bool state = false;        private void btnStart_Click(object sender, EventArgs e)        {            if (!state)            {                Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);                serverSocket = socket;                //ip port                socket.Bind(new IPEndPoint(IPAddress.Parse(txtIP.Text.ToString()), int.Parse(txtPort.Text)));                //listen                socket.Listen(10);//连接等待队列                ThreadPool.QueueUserWorkItem(new WaitCallback(this.AcceptClientConnect), socket);                state = true;                btnStart.Text = "停止服务";            }            else            {                try                {                    serverSocket.Close();                    serverSocket.Shutdown(SocketShutdown.Both);                }                catch (Exception)                {                    state = false;                    btnStart.Text = "开始服务";                }                                                            }            //对象                   }        //日志文本框追加数据        public void AppendTextToTxtLog(string txt)        {            if (txtLog.InvokeRequired)            {                txtLog.BeginInvoke(new Action<string>(s =>                {                    this.txtLog.Text = string.Format("{0}\r\n{1}", s, txtLog.Text);                }), txt);            }            else            {                this.txtLog.Text = string.Format("{0}\r\n{1}", txt, txtLog.Text);            }        }        public void AcceptClientConnect(object socket)        {            var serverSocket = socket as Socket;            this.AppendTextToTxtLog("服务器端开始接受客户端的链接");            while (true)            {                try                {                    var proxSocket = serverSocket.Accept();                    this.AppendTextToTxtLog(string.Format("客户端{0}连接上了", proxSocket.RemoteEndPoint.ToString()));                    ClientProxClentList.Add(proxSocket);                    //接受消息                    ThreadPool.QueueUserWorkItem(new WaitCallback(this.ReceiveData), proxSocket);                }                catch (Exception)                {                }                            }        }        public void ReceiveData(object obj)        {            Socket proxSocket = obj as Socket;            byte[] data = new byte[1024 * 1024];            while (true)            {                int readLen = 0;                try                {                    readLen = proxSocket.Receive(data, 0, data.Length, SocketFlags.None);                }                catch (Exception ex)                {                    //异常退出时                    AppendTextToTxtLog(string.Format("客户端{0}非正常退出", proxSocket.RemoteEndPoint.ToString()));                    ClientProxClentList.Remove(proxSocket);                    StopConnetct(proxSocket);                    return;                }                if (readLen<=0)                {                    //客户端正常退出                    AppendTextToTxtLog(string.Format("客户端:{0}正常退出", proxSocket.RemoteEndPoint.ToString()));                    ClientProxClentList.Remove(proxSocket);                    StopConnetct(proxSocket);                    return;//方法结束->终结当前接受客户端数据的异步线程                }                string txt = Encoding.Default.GetString(data, 0, readLen);                AppendTextToTxtLog(string.Format("接收到客户端{0}的消息{1}",proxSocket.RemoteEndPoint.ToString(),txt));            }        }        private void btnSend_Click(object sender, EventArgs e)        {            foreach (var proxSocket in ClientProxClentList)            {                if (proxSocket.Connected)                {                    //原始的字符串转换成的字节数组                    byte[] data = Encoding.Default.GetBytes(txtSendMsg.Text);                    //在头部加上标记字节                    byte[] result = new byte[data.Length + 1];                    //头部协议字节 1:代表字符串                    result[0] = 1;                    Buffer.BlockCopy(data, 0, result, 1, data.Length);                    proxSocket.Send(result, 0, result.Length,SocketFlags.None);                }            }        }        private void StopConnetct(Socket proxSocket)        {            try            {                if (proxSocket.Connected)                {                    proxSocket.Shutdown(SocketShutdown.Both);                    proxSocket.Close(100);                }            }            catch (Exception ex)            {            }        }        private void button2_Click(object sender, EventArgs e)        {            using (OpenFileDialog ofd =new OpenFileDialog())            {                if (ofd.ShowDialog()!=DialogResult.OK)                {                    return;                }                byte[] data = File.ReadAllBytes(ofd.FileName);                byte[] result = new byte[data.Length + 1];                result[0] = 3;                Buffer.BlockCopy(data, 0, result, 1,data.Length);                foreach (var proxSocket in ClientProxClentList)                {                    if (!proxSocket.Connected)                    {                        continue;                    }                    proxSocket.Send(result, SocketFlags.None);                }            }                   }        private void button1_Click(object sender, EventArgs e)        {            foreach (var proxSocket in ClientProxClentList)            {                if (proxSocket.Connected)                {                    proxSocket.Send(new byte[] { 2 }, SocketFlags.None);                }            }        }    }}

现在开始客户端的代码

点击按钮连接Server,在外面创建一个socket对象名称为ClientSocket.方便其他地方调用,连接成功后new一个线程名称thread来处理接受到的消息,注意.thread设置为后台线程thread.IsBackground = true,线程开始的时候把当前的socket对象作为参数给它,thread.Start(ClientSocket);

private void btnConnect_Click(object sender, EventArgs e)        {            Socket socket = new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);            ClientSocket = socket;            try            {                socket.Connect(IPAddress.Parse(txtIP.Text), int.Parse(txtPort.Text));            }            catch (Exception ex)            {                                MessageBox.Show("Bad");                return;            }                        AppendTextToTxtLog(string.Format("服务端{0}已连接",ClientSocket.RemoteEndPoint.ToString()));            Thread thread = new Thread(new ParameterizedThreadStart(ReceiveData));            thread.IsBackground = true;            thread.Start(ClientSocket);        }

消息接受方法ReceiveData(), socket对象.Receive(data, 0, data.Length, SocketFlags.None);返回值是实际接受的字节流长度,变量名readLen,后面要用.

public void ReceiveData(object obj)        {            Socket proxSocket = obj as Socket;            byte[] data = new byte[1024 * 1024];            while (true)            {                int readLen = 0;                try                {                    readLen = proxSocket.Receive(data, 0, data.Length, SocketFlags.None);                }                catch (Exception)                {                    //异常退出时                    AppendTextToTxtLog(string.Format("服务端{0}非正常退出", proxSocket.RemoteEndPoint.ToString()));                    StopConnetct();                    return;                }                if (readLen <= 0)                {                    //客户端正常退出                    AppendTextToTxtLog(string.Format("服务端:{0}正常退出", proxSocket.RemoteEndPoint.ToString()));                                        StopConnetct();                    return;//方法结束->终结当前接受客户端数据的异步线程                }                //接受的数据中第一个字节如果是1,那么是字符串.2是闪屏.3是文件                if (data[0]==1)                {                    string strMsg = ProcessRecieveString(data, readLen);                    AppendTextToTxtLog(string.Format("接收到服务端{0}的消息{1}", proxSocket.RemoteEndPoint.ToString(), strMsg));                }                else if (data[0] == 2)                {                    ProcessRecieveShake();                }                else if (data[0]==3)                {                    ProcessRecieveFile(data, readLen);                }            }        }

下面是对字节流首位分别是1,2,3的处理方法

 public string ProcessRecieveString(byte[] data,int readLen)        {            string str = Encoding.Default.GetString(data, 1, readLen);            return str;        }        public void ProcessRecieveShake()        {            Point oldLocation = this.Location;            Random r = new Random();                        if (this.InvokeRequired)            {                txtLog.BeginInvoke(new Action<Point,Random>(Shake),oldLocation,r);            }            else            {                Shake(oldLocation, r);            }                 }        private void Shake(Point oldLocation, Random r)        {            for (int i = 0; i < 50; i++)            {                this.Location = new Point(r.Next(oldLocation.X - 5, oldLocation.X + 5), r.Next(oldLocation.Y - 5, oldLocation.Y + 5));                Thread.Sleep(50);                this.Location = oldLocation;            }        }        public void ProcessRecieveFile(byte[] data,int readLen)        {            using (SaveFileDialog sfd = new SaveFileDialog())            {                sfd.DefaultExt = "txt";                sfd.Filter = "文本文件(*.txt)|*.txt|所有文件(*.*)|*.*";                if (sfd.ShowDialog(this) != DialogResult.OK)                {                    return;                }                byte[] fileData = new byte[readLen - 1];                Buffer.BlockCopy(data, 1, fileData, 0, readLen - 1);                File.WriteAllBytes(sfd.FileName, fileData);                AppendTextToTxtLog(string.Format("接收到文件,已保存到{0}", sfd.FileName));            }        }

下面是发送消息的代码(和服务端的基本差不多)

 private void btnSend_Click(object sender, EventArgs e)        {            // AppendTextToTxtLog("123");            if (ClientSocket==null)            {                return;            }            if (ClientSocket.Connected)            {                byte[] data = Encoding.Default.GetBytes(txtSendMsg.Text);                ClientSocket.Send(data, 0, data.Length, SocketFlags.None);            }                    }

下面是客户端的整体代码

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 SocketClient{    public partial class Mianfrm : Form    {        public Mianfrm()        {            InitializeComponent();            //Control.CheckForIllegalCrossThreadCalls = false;        }        public Socket ClientSocket { get; set;   }        private void btnConnect_Click(object sender, EventArgs e)        {            Socket socket = new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);            ClientSocket = socket;            try            {                socket.Connect(IPAddress.Parse(txtIP.Text), int.Parse(txtPort.Text));            }            catch (Exception ex)            {                                MessageBox.Show("Bad");                return;            }                        AppendTextToTxtLog(string.Format("服务端{0}已连接",ClientSocket.RemoteEndPoint.ToString()));            Thread thread = new Thread(new ParameterizedThreadStart(ReceiveData));            thread.IsBackground = true;            thread.Start(ClientSocket);        }        public void ReceiveData(object obj)        {            Socket proxSocket = obj as Socket;            byte[] data = new byte[1024 * 1024];            while (true)            {                int readLen = 0;                try                {                    readLen = proxSocket.Receive(data, 0, data.Length, SocketFlags.None);                }                catch (Exception)                {                    //异常退出时                    AppendTextToTxtLog(string.Format("服务端{0}非正常退出", proxSocket.RemoteEndPoint.ToString()));                    StopConnetct();                    return;                }                if (readLen <= 0)                {                    //客户端正常退出                    AppendTextToTxtLog(string.Format("服务端:{0}正常退出", proxSocket.RemoteEndPoint.ToString()));                                        StopConnetct();                    return;//方法结束->终结当前接受客户端数据的异步线程                }                //接受的数据中第一个字节如果是1,那么是字符串.2是闪屏.3是文件                if (data[0]==1)                {                    string strMsg = ProcessRecieveString(data, readLen);                    AppendTextToTxtLog(string.Format("接收到服务端{0}的消息{1}", proxSocket.RemoteEndPoint.ToString(), strMsg));                }                else if (data[0] == 2)                {                    ProcessRecieveShake();                }                else if (data[0]==3)                {                    ProcessRecieveFile(data, readLen);                }            }        }        public string ProcessRecieveString(byte[] data,int readLen)        {            string str = Encoding.Default.GetString(data, 1, readLen);            return str;        }        public void ProcessRecieveShake()        {            Point oldLocation = this.Location;            Random r = new Random();                        if (this.InvokeRequired)            {                txtLog.BeginInvoke(new Action<Point,Random>(Shake),oldLocation,r);            }            else            {                Shake(oldLocation, r);            }                 }        private void Shake(Point oldLocation, Random r)        {            for (int i = 0; i < 50; i++)            {                this.Location = new Point(r.Next(oldLocation.X - 5, oldLocation.X + 5), r.Next(oldLocation.Y - 5, oldLocation.Y + 5));                Thread.Sleep(50);                this.Location = oldLocation;            }        }        public void ProcessRecieveFile(byte[] data,int readLen)        {            using (SaveFileDialog sfd = new SaveFileDialog())            {                sfd.DefaultExt = "txt";                sfd.Filter = "文本文件(*.txt)|*.txt|所有文件(*.*)|*.*";                if (sfd.ShowDialog(this) != DialogResult.OK)                {                    return;                }                byte[] fileData = new byte[readLen - 1];                Buffer.BlockCopy(data, 1, fileData, 0, readLen - 1);                File.WriteAllBytes(sfd.FileName, fileData);                AppendTextToTxtLog(string.Format("接收到文件,已保存到{0}", sfd.FileName));            }        }        public void AppendTextToTxtLog(string txt)        {            if (txtLog.InvokeRequired)            {                txtLog.BeginInvoke(new Action<string>(s =>{this.txtLog.Text = String.Format("{0}\r\n{1}", s, txtLog.Text);}), txt);            }            else            {                this.txtLog.Text = string.Format("{0}\r\n{1}", txt, txtLog.Text);            }        }        private void btnSend_Click(object sender, EventArgs e)        {            // AppendTextToTxtLog("123");            if (ClientSocket==null)            {                return;            }            if (ClientSocket.Connected)            {                byte[] data = Encoding.Default.GetBytes(txtSendMsg.Text);                ClientSocket.Send(data, 0, data.Length, SocketFlags.None);            }                    }        private void StopConnetct()        {            try            {                if (ClientSocket.Connected)                {                    ClientSocket.Shutdown(SocketShutdown.Both);                    ClientSocket.Close(100);                }            }            catch (Exception ex)            {            }        }        private void Mianfrm_FormClosing(object sender, FormClosingEventArgs e)        {            StopConnetct();        }        private void Mianfrm_Load(object sender, EventArgs e)        {            AppendTextToTxtLog("请单击连接到服务器");        }    }}

最后是软件的界面,控件命名看名字基本就知道了,欢迎讨论