C# Socket 实现文字传输

通信基本流程：

服务端：

创建一个用于监听连接的Socket对象
用指定的ip地址和端口建立一个EndPoint对象（相当于Socket的端点）
用Socket的Bind()方法绑定EndPoint
用Socket的Listen()方法开始监听
接收到客户端的连接，用Socket的Accept()创建一个新的用于和客户端进行通信的Socket
通信结束关闭Socket
客户端：

建立一个Socket对象
用指定的ip地址和端口建立一个EndPoint对象（相当于Socket的端点）
用Socket对象的Connect()方法（EndPoint为参数）向服务器发出连接请求
如果连接成功，就用Socket对象的Send()方法向服务器发送信息
用Socket对象的Send()方法接收信息
通信结束关闭Socket
服务端界面：

 服务端界面设计源码

namespace SocketString
{
    partial class Form1
    {
        /// <summary>
        /// 必需的设计器变量。
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// 清理所有正在使用的资源。
        /// </summary>
        /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows 窗体设计器生成的代码

        /// <summary>
        /// 设计器支持所需的方法 - 不要修改
        /// 使用代码编辑器修改此方法的内容。
        /// </summary>
        private void InitializeComponent()
        {
            this.button1 = new System.Windows.Forms.Button();
            this.button2 = new System.Windows.Forms.Button();
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.textBox2 = new System.Windows.Forms.TextBox();
            this.button3 = new System.Windows.Forms.Button();
            this.textBox3 = new System.Windows.Forms.TextBox();
            this.textBox4 = new System.Windows.Forms.TextBox();
            this.SuspendLayout();
            // 
            // button1
            // 
            this.button1.Location = new System.Drawing.Point(315, 28);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(75, 23);
            this.button1.TabIndex = 0;
            this.button1.Text = "开始监听";
            this.button1.UseVisualStyleBackColor = true;
            this.button1.Click += new System.EventHandler(this.button1_Click);
            // 
            // button2
            // 
            this.button2.Location = new System.Drawing.Point(425, 28);
            this.button2.Name = "button2";
            this.button2.Size = new System.Drawing.Size(75, 23);
            this.button2.TabIndex = 1;
            this.button2.Text = "停止监听";
            this.button2.UseVisualStyleBackColor = true;
            // 
            // textBox1
            // 
            this.textBox1.Location = new System.Drawing.Point(27, 28);
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(100, 21);
            this.textBox1.TabIndex = 2;
            this.textBox1.Text = "127.0.0.1";
            // 
            // textBox2
            // 
            this.textBox2.Location = new System.Drawing.Point(158, 28);
            this.textBox2.Name = "textBox2";
            this.textBox2.Size = new System.Drawing.Size(100, 21);
            this.textBox2.TabIndex = 3;
            this.textBox2.Text = "8081";
            // 
            // button3
            // 
            this.button3.Location = new System.Drawing.Point(532, 206);
            this.button3.Name = "button3";
            this.button3.Size = new System.Drawing.Size(75, 23);
            this.button3.TabIndex = 6;
            this.button3.Text = "发送消息";
            this.button3.UseVisualStyleBackColor = true;
            this.button3.Click += new System.EventHandler(this.button3_Click);
            // 
            // textBox3
            // 
            this.textBox3.Location = new System.Drawing.Point(51, 76);
            this.textBox3.Multiline = true;
            this.textBox3.Name = "textBox3";
            this.textBox3.Size = new System.Drawing.Size(463, 98);
            this.textBox3.TabIndex = 7;
            // 
            // textBox4
            // 
            this.textBox4.Location = new System.Drawing.Point(51, 206);
            this.textBox4.Multiline = true;
            this.textBox4.Name = "textBox4";
            this.textBox4.Size = new System.Drawing.Size(463, 116);
            this.textBox4.TabIndex = 8;
            // 
            // Form1
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(800, 450);
            this.Controls.Add(this.textBox4);
            this.Controls.Add(this.textBox3);
            this.Controls.Add(this.button3);
            this.Controls.Add(this.textBox2);
            this.Controls.Add(this.textBox1);
            this.Controls.Add(this.button2);
            this.Controls.Add(this.button1);
            this.Name = "Form1";
            this.Text = "Form1";
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private System.Windows.Forms.Button button1;
        private System.Windows.Forms.Button button2;
        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.TextBox textBox2;
        private System.Windows.Forms.Button button3;
        private System.Windows.Forms.TextBox textBox3;
        private System.Windows.Forms.TextBox textBox4;
    }
}

服务端后台逻辑源码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
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 SocketString
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        //定义回调:解决跨线程访问问题
        private delegate void SetTextValueCallBack(string strValue);
        //定义接收客户端发送消息的回调
        private delegate void ReceiveMsgCallBack(string strReceive);
        //声明回调
        private SetTextValueCallBack setCallBack;
        //声明
        private ReceiveMsgCallBack receiveCallBack;
        //定义回调：给ComboBox控件添加元素
        private delegate void SetCmbCallBack(string strItem);
        //声明
        private SetCmbCallBack setCmbCallBack;
        //定义发送文件的回调
        private delegate void SendFileCallBack(byte[] bf);
        //声明
        private SendFileCallBack sendCallBack;

        //用于通信的Socket
        Socket socketSend;
        //用于监听的SOCKET
        Socket socketWatch;

        //将远程连接的客户端的IP地址和Socket存入集合中
        Dictionary<string, Socket> dicSocket = new Dictionary<string, Socket>();

        //创建监听连接的线程
        Thread AcceptSocketThread;
        //接收客户端发送消息的线程
        Thread threadReceive;

        /// <summary>
        /// 开始监听
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button1_Click(object sender, EventArgs e)
        {
            //当点击开始监听的时候 在服务器端创建一个负责监听IP地址和端口号的Socket
            socketWatch = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            //获取ip地址
            IPAddress ip = IPAddress.Parse(this.textBox1.Text.Trim());
            //创建端口号, EndPoint对象
            IPEndPoint point = new IPEndPoint(ip, Convert.ToInt32(this.textBox2.Text.Trim()));
            //绑定IP地址和端口号
            socketWatch.Bind(point);
            this.textBox3.AppendText("监听成功" + " 
 
");
            //开始监听:设置最大可以同时连接多少个请求
            socketWatch.Listen(10);

            //实例化回调
            setCallBack = new SetTextValueCallBack(SetTextValue);
            receiveCallBack = new ReceiveMsgCallBack(ReceiveMsg);
            //setCmbCallBack = new SetCmbCallBack(AddCmbItem);

            //创建线程
            AcceptSocketThread = new Thread(new ParameterizedThreadStart(StartListen));
            AcceptSocketThread.IsBackground = true;
            AcceptSocketThread.Start(socketWatch);
        }


        /// <summary>
        /// 等待客户端的连接，并且创建与之通信用的Socket
        /// </summary>
        /// <param name="obj"></param>
        private void StartListen(object obj)
        {
            Socket socketWatch = obj as Socket;
            while (true)
            {
                //等待客户端的连接，并且创建一个用于通信的Socket
                socketSend = socketWatch.Accept();
                //获取远程主机的ip地址和端口号
                strIp = socketSend.RemoteEndPoint.ToString();
                dicSocket.Add(strIp, socketSend);
                //this.listBox1.Invoke(setCmbCallBack, strIp);
                string strMsg = "远程主机：" + socketSend.RemoteEndPoint + "连接成功";
                //使用回调
                textBox3.Invoke(setCallBack, strMsg);

                //定义接收客户端消息的线程
                Thread threadReceive = new Thread(new ParameterizedThreadStart(Receive));
                threadReceive.IsBackground = true;
                threadReceive.Start(socketSend);
            }
        }
        string strIp;

        /// <summary>
        /// 服务器给客户端发送消息
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button3_Click(object sender, EventArgs e)
        {
            try
            {
                string strMsg = this.textBox4.Text.Trim();
                byte[] buffer = Encoding.Default.GetBytes(strMsg);

                List<byte> list = new List<byte>();
                list.Add(0);
                list.AddRange(buffer);
                //将泛型集合转换为数组
                byte[] newBuffer = list.ToArray();
                //获得用户选择的IP地址
                string ip = strIp;
                dicSocket[ip].Send(newBuffer);
            }
            catch (Exception ex)
            {
                MessageBox.Show("给客户端发送消息出错:" + ex.Message);
            }
            //socketSend.Send(buffer);
        }

        /// <summary>
        /// 服务器端不停的接收客户端发送的消息
        /// </summary>
        /// <param name="obj"></param>
        private void Receive(object obj)
        {
            Socket socketSend = obj as Socket;
            while (true)
            {
                //客户端连接成功后，服务器接收客户端发送的消息
                byte[] buffer = new byte[2048];
                //实际接收到的有效字节数
                int count = socketSend.Receive(buffer);
                if (count == 0)//count 表示客户端关闭，要退出循环
                {
                    break;
                }
                else
                {
                    string str = Encoding.Default.GetString(buffer, 0, count);
                    string strReceiveMsg = "接收：" + socketSend.RemoteEndPoint + "发送的消息:" + str + "
";
                    textBox3.Invoke(receiveCallBack, strReceiveMsg);
                }
            }
        }

        /// <summary>
        /// 停止监听
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button2_Click(object sender, EventArgs e)
        {
            socketWatch.Close();
            socketSend.Close();
            //终止线程
            AcceptSocketThread.Abort();
            threadReceive.Abort();
        }


        /// <summary>
        /// 回调委托需要执行的方法
        /// </summary>
        /// <param name="strValue"></param>
        private void SetTextValue(string strValue)
        {
            this.textBox3.AppendText(strValue + " 
 
");
        }


        private void ReceiveMsg(string strMsg)
        {
            this.textBox3.AppendText(strMsg + " 
 
");
        }

}
}

客户端界面

客户端设计源码

namespace SocketStringServer
{
    partial class Form1
    {
        /// <summary>
        /// 必需的设计器变量。
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// 清理所有正在使用的资源。
        /// </summary>
        /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows 窗体设计器生成的代码

        /// <summary>
        /// 设计器支持所需的方法 - 不要修改
        /// 使用代码编辑器修改此方法的内容。
        /// </summary>
        private void InitializeComponent()
        {
            this.textBox4 = new System.Windows.Forms.TextBox();
            this.textBox3 = new System.Windows.Forms.TextBox();
            this.button3 = new System.Windows.Forms.Button();
            this.textBox2 = new System.Windows.Forms.TextBox();
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.button2 = new System.Windows.Forms.Button();
            this.button1 = new System.Windows.Forms.Button();
            this.SuspendLayout();
            // 
            // textBox4
            // 
            this.textBox4.Location = new System.Drawing.Point(134, 256);
            this.textBox4.Multiline = true;
            this.textBox4.Name = "textBox4";
            this.textBox4.Size = new System.Drawing.Size(463, 116);
            this.textBox4.TabIndex = 15;
            // 
            // textBox3
            // 
            this.textBox3.Location = new System.Drawing.Point(134, 126);
            this.textBox3.Multiline = true;
            this.textBox3.Name = "textBox3";
            this.textBox3.Size = new System.Drawing.Size(463, 98);
            this.textBox3.TabIndex = 14;
            // 
            // button3
            // 
            this.button3.Location = new System.Drawing.Point(598, 386);
            this.button3.Name = "button3";
            this.button3.Size = new System.Drawing.Size(75, 23);
            this.button3.TabIndex = 13;
            this.button3.Text = "发送消息";
            this.button3.UseVisualStyleBackColor = true;
            this.button3.Click += new System.EventHandler(this.button3_Click);
            // 
            // textBox2
            // 
            this.textBox2.Location = new System.Drawing.Point(241, 78);
            this.textBox2.Name = "textBox2";
            this.textBox2.Size = new System.Drawing.Size(100, 21);
            this.textBox2.TabIndex = 12;
            this.textBox2.Text = "8081";
            // 
            // textBox1
            // 
            this.textBox1.Location = new System.Drawing.Point(110, 78);
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(100, 21);
            this.textBox1.TabIndex = 11;
            this.textBox1.Text = "127.0.0.1";
            // 
            // button2
            // 
            this.button2.Location = new System.Drawing.Point(508, 78);
            this.button2.Name = "button2";
            this.button2.Size = new System.Drawing.Size(75, 23);
            this.button2.TabIndex = 10;
            this.button2.Text = "断开连接";
            this.button2.UseVisualStyleBackColor = true;
            this.button2.Click += new System.EventHandler(this.button2_Click);
            // 
            // button1
            // 
            this.button1.Location = new System.Drawing.Point(398, 78);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(75, 23);
            this.button1.TabIndex = 9;
            this.button1.Text = "连接";
            this.button1.UseVisualStyleBackColor = true;
            this.button1.Click += new System.EventHandler(this.button1_Click);
            // 
            // Form1
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(800, 450);
            this.Controls.Add(this.textBox4);
            this.Controls.Add(this.textBox3);
            this.Controls.Add(this.button3);
            this.Controls.Add(this.textBox2);
            this.Controls.Add(this.textBox1);
            this.Controls.Add(this.button2);
            this.Controls.Add(this.button1);
            this.Name = "Form1";
            this.Text = "Form1";
            this.Load += new System.EventHandler(this.Form1_Load);
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private System.Windows.Forms.TextBox textBox4;
        private System.Windows.Forms.TextBox textBox3;
        private System.Windows.Forms.Button button3;
        private System.Windows.Forms.TextBox textBox2;
        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.Button button2;
        private System.Windows.Forms.Button button1;
    }
}

客户端后台逻辑源码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
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 SocketStringServer
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        //定义回调
        private delegate void SetTextCallBack(string strValue);
        //声明
        private SetTextCallBack setCallBack;

        //定义接收服务端发送消息的回调
        private delegate void ReceiveMsgCallBack(string strMsg);
        //声明
        private ReceiveMsgCallBack receiveCallBack;

        //创建连接的Socket
        Socket socketSend;
        //创建接收客户端发送消息的线程
        Thread threadReceive;


        /// <summary>
        /// 连接
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                socketSend = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
                IPAddress ip = IPAddress.Parse(this.textBox1.Text.Trim());
                socketSend.Connect(ip, Convert.ToInt32(this.textBox2.Text.Trim()));
                //实例化回调
                setCallBack = new SetTextCallBack(SetValue);
                receiveCallBack = new ReceiveMsgCallBack(SetValue);
                this.textBox3.Invoke(setCallBack, "连接成功");

                //开启一个新的线程不停的接收服务器发送消息的线程
                threadReceive = new Thread(new ThreadStart(Receive));
                //设置为后台线程
                threadReceive.IsBackground = true;
                threadReceive.Start();
            }
            catch (Exception ex)
            {
                MessageBox.Show("连接服务端出错:" + ex.ToString());
            }
        }


        /// <summary>
        /// 接收服务器发送的消息
        /// </summary>
        private void Receive()
        {
            try
            {
                while (true)
                {
                    byte[] buffer = new byte[2048];
                    //实际接收到的字节数
                    int r = socketSend.Receive(buffer);
                    if (r == 0)
                    {
                        break;
                    }
                    else
                    {
                        //判断发送的数据的类型
                        if (buffer[0] == 0)//表示发送的是文字消息
                        {
                            string str = Encoding.Default.GetString(buffer, 1, r - 1);
                            this.textBox3.Invoke(receiveCallBack, "接收远程服务器:" + socketSend.RemoteEndPoint + "发送的消息:" + str + "
");
                        }
                    }


                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("接收服务端发送的消息出错:" + ex.ToString());
            }
        }

        private void SetValue(string strValue)
        {
            this.textBox3.AppendText(strValue + "
 
");
        }

        /// <summary>
        /// 客户端给服务器发送消息
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button3_Click(object sender, EventArgs e)
        {
            try
            {
                string strMsg = this.textBox4.Text.Trim();
                byte[] buffer = new byte[2048];
                buffer = Encoding.Default.GetBytes(strMsg);
                int receive = socketSend.Send(buffer);
            }
            catch (Exception ex)
            {
                MessageBox.Show("发送消息出错:" + ex.Message);
            }
        }
        private void Form1_Load(object sender, EventArgs e)
        {
            Control.CheckForIllegalCrossThreadCalls = false;
        }
        /// <summary>
        /// 断开连接
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button2_Click(object sender, EventArgs e)
        {
            //关闭socket
            socketSend.Close();
            //终止线程
            threadReceive.Abort();
        }

     
    }
}

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