C#-WebSocket协议通讯_Net5

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  代码地址:https://gitee.com/qq28069933146_admin/csharp_networkprotocol_research

  视频地址:

一、WebSocket知识点

1、侦听

  (1)使用httpListener进行侦听

  (2)若侦听到的内容是WebSocket协议,即httpListener.GetContextAsync().Request.IsWebSocketRequest,则对内容进行处理

        private static HttpListener httpListener = new HttpListener();    // HttpListener

        /// <summary>
        /// 开启Socket服务,对参数地址进行监听
        /// </summary>
        /// <param name="ipAdress">监听地址,记得以 / 结尾</param>
        private async void Start(string ipAdress)
        
            try
            
                httpListener.Prefixes.Add(ipAdress); // 添加监听的URL范围
                // 通过连接名称可以区分多个websocket服务。如可以通过 http://localhost:8080/learn http://localhost:8080/work 使用两个服务,不过需要多线程和两个http监听对象等
                httpListener.Start();
                lblListen.Text = "监听中...";
                while (true)
                
                    // http端口监听获取内容
                    HttpListenerContext httpListenerContext = await httpListener.GetContextAsync();
                    if (httpListenerContext.Request.IsWebSocketRequest)  // 如果是websocket请求
                    
                        // 处理SocketRequest
                        ProcessRequest(httpListenerContext);
                    
                    else
                    
                        httpListenerContext.Response.StatusCode = 400;
                        httpListenerContext.Response.Close();
                    
                
            
            catch (Exception ex)
            
                txtInfo.AppendText(ex.ToString() + DateTime.Now.ToString() + "\\n");
            
        

2、侦听-处理内容并维护WebSocket客户端连接

        /// <summary>
        /// 处理端口监听到的请求
        /// </summary>
        /// <param name="httpListenerContext"></param>
        private async void ProcessRequest(HttpListenerContext httpListenerContext)
        
            WebSocketContext webSocketContext = null;  // WebSocketContext 类用于访问websocket握手中的信息
            try
            
                webSocketContext = await httpListenerContext.AcceptWebSocketAsync(subProtocol: null);  // 配置协议为空
                // 获取客户端IP
                string ipAddress = httpListenerContext.Request.RemoteEndPoint.Address.ToString();
                txtInfo.AppendText("客户端IP地址:" + ipAddress + "\\n");
            
            catch (Exception e)  // 如果出错
            
                httpListenerContext.Response.StatusCode = 500;
                httpListenerContext.Response.Close();
                txtInfo.AppendText("Exception:" + e.ToString() + DateTime.Now.ToString() + "\\n");
                return;
            
            // 获取websocket连接
            WebSocket webSocket = webSocketContext.WebSocket;
            _sockets.Add(webSocket);         // 此处将web socket对象加入一个静态列表中
            SendToNewConnection(webSocket);  // 将当前服务器上最新的数据(a,b的值)发送过去

            try
            
                // 我们定义一个常数,它将表示接收到的数据的大小。 它是由我们建立的,我们可以设定任何值。 我们知道在这种情况下,发送的数据的大小非常小。
                const int maxMessageSize = 2048;
                // received bits的缓冲区

                while (webSocket != null && webSocket.State == WebSocketState.Open)  // 如果连接是打开的
                
                    // 此句放在while里面,每次使用都重新初始化。如果放在外面,由于没有进行清空操作,下一次接收的数据若比上一次短,则会多出一部分内容。
                    var receiveBuffer = new ArraySegment<Byte>(new Byte[maxMessageSize]);

                    WebSocketReceiveResult receiveResult = null;
                    byte[] payloadData = null;
                    do
                    
                        // 读取数据。此类的实例表示在 WebSocket 上执行单个 ReceiveAsync 操作所得到的结果
                        receiveResult = await webSocket.ReceiveAsync(receiveBuffer, CancellationToken.None);
                        // 字节数组
                        payloadData = receiveBuffer.Array.Where(b => b != 0).ToArray();
                    
                    while (!receiveResult.EndOfMessage);  // 如果指示已完整接收消息则停止

                    // 如果输入帧为取消帧,发送close命令。
                    // MessageType指示当前消息是utf-8消息还是二进制信息。Text(0,明文形式),Close(2,收到关闭消息,接受已完成),Binary(1,消息采用二进制格式)
                    if (receiveResult.MessageType == WebSocketMessageType.Close)
                    
                        await webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, String.Empty, CancellationToken.None);
                        _sockets.Remove(webSocket);  // 从列表移除当前连接

                    
                    else
                    
                        // 因为我们知道这是一个字符串,我们转换它                        
                        string receiveString = System.Text.Encoding.UTF8.GetString(payloadData, 0, payloadData.Length);

                        try  // 将反序列化内容放入try中,避免无法匹配、内容为空等可能报错的地方
                        
                            // 将转换后的字符串内容进行json反序列化。参考:https://www.cnblogs.com/yinmu/p/12160343.html
                            TestValue tv = JsonConvert.DeserializeObject<TestValue>(receiveString);
                            // 将收到的a,b的值显示到文本框
                            if (tv != null)
                            
                                string valueA = string.Empty, valueB = string.Empty;
                                if (tv.a != null && tv.a.Length > 0)  valueA = tv.a; 
                                if (tv.a != null && tv.b.Length > 0)  valueB = tv.b; 
                                txtAvalue.Text = valueA;
                                txtBvalue.Text = valueB;
                            

                            RefreshConnectionList();  // 先清理无效的连接,否则会导致服务端websocket被dispose

                            //  当接收到文本消息时,对当前服务器上所有web socket连接进行广播
                            foreach (var innerSocket in _sockets)
                            
                                await innerSocket.SendAsync(new ArraySegment<byte>(payloadData), WebSocketMessageType.Text, true, CancellationToken.None);
                            
                        
                        catch (Exception ex)
                        
                            // 如果json反序列化出了问题
                            txtInfo.AppendText(ex.ToString() + DateTime.Now.ToString() + "\\n");  // 将错误类型显示出来
                            txtInfo.AppendText(receiveString + DateTime.Now.ToString() + "\\n");  // 将收到的原始字符串显示出来
                        
                    
                
            
            catch (Exception e)
            
                if (e.GetType().ToString() == "System.Net.WebSockets.WebSocketException")
                
                    // 客户端关闭时会抛出此错误
                    txtInfo.AppendText("连接已关闭" + DateTime.Now.ToString() + "\\n");
                
                else
                
                    txtInfo.AppendText(e.ToString() + DateTime.Now.ToString() + "\\n");
                
            
        

3、发送

WebSocket webSocket=webSocketContext.WebSocket;

// 发送信息
string jsonmessage="信息内容";  // 信息内容
Byte[] bytes = System.Text.Encoding.UTF8.GetBytes(jsonmessage);
webSocket.SendAsync(new ArraySegment<byte>(bytes), WebSocketMessageType.Text, true, CancellationToken.None);  // 发送

二、完整示例

1、服务器端:

(1)WinSocketServer1.Designer.cs

查看代码
 
namespace WinSocketServer

    partial class WinSocketServer1
    
        /// <summary>
        ///  Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        ///  Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        
            if (disposing && (components != null))
            
                components.Dispose();
            
            base.Dispose(disposing);
        

        #region Windows Form Designer generated code

        /// <summary>
        ///  Required method for Designer support - do not modify
        ///  the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        
            btnModify = new System.Windows.Forms.Button();
            label1 = new System.Windows.Forms.Label();
            txtIPAddress = new System.Windows.Forms.TextBox();
            label2 = new System.Windows.Forms.Label();
            label3 = new System.Windows.Forms.Label();
            txtAvalue = new System.Windows.Forms.TextBox();
            txtBvalue = new System.Windows.Forms.TextBox();
            btnBroadcast = new System.Windows.Forms.Button();
            panel1 = new System.Windows.Forms.Panel();
            btnClose = new System.Windows.Forms.Button();
            btnOpenServer = new System.Windows.Forms.Button();
            txtInfo = new System.Windows.Forms.TextBox();
            btnShowCon = new System.Windows.Forms.Button();
            lblListen = new System.Windows.Forms.Label();
            panel1.SuspendLayout();
            SuspendLayout();
            // 
            // btnModify
            // 
            btnModify.Location = new System.Drawing.Point(271, 10);
            btnModify.Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            btnModify.Name = "btnModify";
            btnModify.Size = new System.Drawing.Size(73, 25);
            btnModify.TabIndex = 0;
            btnModify.Text = "修改";
            btnModify.UseVisualStyleBackColor = true;
            btnModify.Click += btnModify_Click;
            // 
            // label1
            // 
            label1.AutoSize = true;
            label1.Location = new System.Drawing.Point(9, 14);
            label1.Margin = new System.Windows.Forms.Padding(2, 0, 2, 0);
            label1.Name = "label1";
            label1.Size = new System.Drawing.Size(56, 17);
            label1.TabIndex = 1;
            label1.Text = "监听地址";
            // 
            // txtIPAddress
            // 
            txtIPAddress.Enabled = false;
            txtIPAddress.Location = new System.Drawing.Point(68, 11);
            txtIPAddress.Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            txtIPAddress.Name = "txtIPAddress";
            txtIPAddress.Size = new System.Drawing.Size(200, 23);
            txtIPAddress.TabIndex = 2;
            txtIPAddress.Text = "http://127.0.0.1:8080/";
            // 
            // label2
            // 
            label2.AutoSize = true;
            label2.Location = new System.Drawing.Point(9, 48);
            label2.Margin = new System.Windows.Forms.Padding(2, 0, 2, 0);
            label2.Name = "label2";
            label2.Size = new System.Drawing.Size(27, 17);
            label2.TabIndex = 3;
            label2.Text = "a:";
            // 
            // label3
            // 
            label3.AutoSize = true;
            label3.Location = new System.Drawing.Point(9, 78);
            label3.Margin = new System.Windows.Forms.Padding(2, 0, 2, 0);
            label3.Name = "label3";
            label3.Size = new System.Drawing.Size(28, 17);
            label3.TabIndex = 4;
            label3.Text = "b:";
            // 
            // txtAvalue
            // 
            txtAvalue.Location = new System.Drawing.Point(68, 45);
            txtAvalue.Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            txtAvalue.Name = "txtAvalue";
            txtAvalue.Size = new System.Drawing.Size(161, 23);
            txtAvalue.TabIndex = 5;
            // 
            // txtBvalue
            // 
            txtBvalue.Location = new System.Drawing.Point(68, 76);
            txtBvalue.Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            txtBvalue.Name = "txtBvalue";
            txtBvalue.Size = new System.Drawing.Size(161, 23);
            txtBvalue.TabIndex = 6;
            // 
            // btnBroadcast
            // 
            btnBroadcast.Font = new System.Drawing.Font("Microsoft YaHei UI", 9F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point);
            btnBroadcast.Location = new System.Drawing.Point(244, 48);
            btnBroadcast.Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            btnBroadcast.Name = "btnBroadcast";
            btnBroadcast.Size = new System.Drawing.Size(100, 48);
            btnBroadcast.TabIndex = 7;
            btnBroadcast.Text = "广播";
            btnBroadcast.UseVisualStyleBackColor = true;
            btnBroadcast.Click += btnBroadcast_Click;
            // 
            // panel1
            // 
            panel1.Controls.Add(btnClose);
            panel1.Controls.Add(btnOpenServer);
            panel1.Location = new System.Drawing.Point(368, 3);
            panel1.Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            panel1.Name = "panel1";
            panel1.Size = new System.Drawing.Size(110, 96);
            panel1.TabIndex = 10;
            // 
            // btnClose
            // 
            btnClose.Location = new System.Drawing.Point(19, 60);
            btnClose.Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            btnClose.Name = "btnClose";
            btnClose.Size = new System.Drawing.Size(73, 25);
            btnClose.TabIndex = 11;
            btnClose.Text = "关闭监听";
            btnClose.UseVisualStyleBackColor = true;
            btnClose.Click += btnClose_Click;
            // 
            // btnOpenServer
            // 
            btnOpenServer.Location = new System.Drawing.Point(19, 11);
            btnOpenServer.Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            btnOpenServer.Name = "btnOpenServer";
            btnOpenServer.Size = new System.Drawing.Size(73, 25);
            btnOpenServer.TabIndex = 10;
            btnOpenServer.Text = "开启监听";
            btnOpenServer.UseVisualStyleBackColor = true;
            btnOpenServer.Click += btnOpenServer_Click;
            // 
            // txtInfo
            // 
            txtInfo.Location = new System.Drawing.Point(9, 121);
            txtInfo.Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            txtInfo.Multiline = true;
            txtInfo.Name = "txtInfo";
            txtInfo.Size = new System.Drawing.Size(604, 252);
            txtInfo.TabIndex = 11;
            // 
            // btnShowCon
            // 
            btnShowCon.Location = new System.Drawing.Point(510, 56);
            btnShowCon.Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            btnShowCon.Name = "btnShowCon";
            btnShowCon.Size = new System.Drawing.Size(92, 39);
            btnShowCon.TabIndex = 12;
            btnShowCon.Text = "显示当前连接";
            btnShowCon.UseVisualStyleBackColor = true;
            btnShowCon.Click += btnShowCon_Click;
            // 
            // lblListen
            // 
            lblListen.AutoSize = true;
            lblListen.Font = new System.Drawing.Font("Microsoft YaHei UI", 9F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point);
            lblListen.Location = new System.Drawing.Point(510, 18);
            lblListen.Margin = new System.Windows.Forms.Padding(2, 0, 2, 0);
            lblListen.Name = "lblListen";
            lblListen.Size = new System.Drawing.Size(92, 17);
            lblListen.TabIndex = 13;
            lblListen.Text = "服务为关闭状态";
            lblListen.TextAlign = System.Drawing.ContentAlignment.TopRight;
            // 
            // WinSocketServer1
            // 
            AutoScaleDimensions = new System.Drawing.SizeF(7F, 17F);
            AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            ClientSize = new System.Drawing.Size(622, 382);
            Controls.Add(lblListen);
            Controls.Add(btnShowCon);
            Controls.Add(txtInfo);
            Controls.Add(panel1);
            Controls.Add(btnBroadcast);
            Controls.Add(txtBvalue);
            Controls.Add(txtAvalue);
            Controls.Add(label3);
            Controls.Add(label2);
            Controls.Add(txtIPAddress);
            Controls.Add(label1);
            Controls.Add(btnModify);
            Margin = new System.Windows.Forms.Padding(2, 3, 2, 3);
            Name = "WinSocketServer1";
            Text = "Win_Socker服务器";
            Load += WinSockerServer1_Load;
            panel1.ResumeLayout(false);
            ResumeLayout(false);
            PerformLayout();
        

        #endregion

        private System.Windows.Forms.Button btnModify;
        private System.Windows.Forms.Label label1;
        private System.Windows.Forms.TextBox txtIPAddress;
        private System.Windows.Forms.Label label2;
        private System.Windows.Forms.Label label3;
        private System.Windows.Forms.TextBox txtAvalue;
        private System.Windows.Forms.TextBox txtBvalue;
        private System.Windows.Forms.Button btnBroadcast;
        private System.Windows.Forms.Panel panel1;
        private System.Windows.Forms.Button btnClose;
        private System.Windows.Forms.Button btnOpenServer;
        private System.Windows.Forms.TextBox txtInfo;
        private System.Windows.Forms.Button btnShowCon;
        private System.Windows.Forms.Label lblListen;
    

(2)WinSocketServer1.cs

using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Net;
using System.Net.WebSockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WinSocketServer

    public partial class WinSocketServer1 : Form
    
        public WinSocketServer1()
        
            InitializeComponent();
        

        private void WinSockerServer1_Load(object sender, EventArgs e)
        

        
        /// <summary>
        /// 打开服务
        /// </summary>
        private void btnOpenServer_Click(object sender, EventArgs e)
        
            if (txtIPAddress.Enabled == true)
            
                MessageBox.Show("请先确认地址");
                return;
            
            string IpAdress = txtIPAddress.Text;
            txtInfo.AppendText("打开监听" + DateTime.Now.ToString() + "\\n");
            Start(IpAdress);
        



        /// <summary>
        /// 关闭服务
        /// </summary>
        private void btnClose_Click(object sender, EventArgs e)
        
            if (httpListener.IsListening)
            
                try
                
                    httpListener.Stop();
                    txtInfo.AppendText("成功关闭" + DateTime.Now.ToString() + "\\n");
                    lblListen.Text = "服务为关闭状态";
                
                catch (Exception ex)
                
                    txtInfo.AppendText(ex.ToString() + DateTime.Now.ToString() + "\\n");
                
            
            else
            
                txtInfo.AppendText("此时服务并未处于监听状态,无法关闭" + DateTime.Now.ToString() + "\\n");
                lblListen.Text = "服务为关闭状态";
                return;
            
        

        /// <summary>
        /// 修改
        /// </summary>
        private void btnModify_Click(object sender, EventArgs e)
        
            if (btnModify.Text == "修改")
            
                txtIPAddress.Enabled = true;
                btnModify.Text = "确定";
            
            else if (btnModify.Text == "确定")
            
                txtIPAddress.Enabled = false;
                btnModify.Text = "修改";
            
        

        /// <summary>
        /// 广播
        /// </summary>
        private void btnBroadcast_Click(object sender, EventArgs e)
        
            string jsonmessage = RequestMsg.SerializeJson(txtAvalue.Text, txtBvalue.Text);
            txtInfo.AppendText("广播" + DateTime.Now.ToString() + ":\\n");
            txtInfo.AppendText("内容:" + jsonmessage + "\\n");
            Broadcast(jsonmessage);
        
        /// <summary>
        /// 显示链接列表
        /// </summary>
        private void btnShowCon_Click(object sender, EventArgs e)
        
            int ConnectionCount = _sockets.Count;
            txtInfo.AppendText("服务端当前存储了" + ConnectionCount + "个客户端连接:\\n" + DateTime.Now.ToString() + "\\n");
            foreach (WebSocket innersocket in _sockets)
            
                txtInfo.AppendText(innersocket.GetHashCode().ToString() + innersocket.State.ToString() + "\\n");
            
        

        #region 监听方法
        private static List<WebSocket> _sockets = new List<WebSocket>();  // 存储当前所有连接的静态列表
        private static HttpListener httpListener = new HttpListener();    // HttpListener

        /// <summary>
        /// 开启Socket服务,对参数地址进行监听
        /// </summary>
        /// <param name="ipAdress">监听地址,记得以 / 结尾</param>
        private async void Start(string ipAdress)
        
            try
            
                httpListener.Prefixes.Add(ipAdress); // 添加监听的URL范围
                // 通过连接名称可以区分多个websocket服务。如可以通过 http://localhost:8080/learn http://localhost:8080/work 使用两个服务,不过需要多线程和两个http监听对象等
                httpListener.Start();
                lblListen.Text = "监听中...";
                while (true)
                
                    // http端口监听获取内容
                    HttpListenerContext httpListenerContext = await httpListener.GetContextAsync();
                    if (httpListenerContext.Request.IsWebSocketRequest)  // 如果是websocket请求
                    
                        // 处理SocketRequest
                        ProcessRequest(httpListenerContext);
                    
                    else
                    
                        httpListenerContext.Response.StatusCode = 400;
                        httpListenerContext.Response.Close();
                    
                
            
            catch (Exception ex)
            
                txtInfo.AppendText(ex.ToString() + DateTime.Now.ToString() + "\\n");
            
        

        /// <summary>
        /// 处理端口监听到的请求
        /// </summary>
        /// <param name="httpListenerContext"></param>
        private async void ProcessRequest(HttpListenerContext httpListenerContext)
        
            WebSocketContext webSocketContext = null;  // WebSocketContext 类用于访问websocket握手中的信息
            try
            
                webSocketContext = await httpListenerContext.AcceptWebSocketAsync(subProtocol: null);  // 配置协议为空
                // 获取客户端IP
                string ipAddress = httpListenerContext.Request.RemoteEndPoint.Address.ToString();
                txtInfo.AppendText("客户端IP地址:" + ipAddress + "\\n");
            
            catch (Exception e)  // 如果出错
            
                httpListenerContext.Response.StatusCode = 500;
                httpListenerContext.Response.Close();
                txtInfo.AppendText("Exception:" + e.ToString() + DateTime.Now.ToString() + "\\n");
                return;
            
            // 获取websocket连接
            WebSocket webSocket = webSocketContext.WebSocket;
            _sockets.Add(webSocket);         // 此处将web socket对象加入一个静态列表中
            SendToNewConnection(webSocket);  // 将当前服务器上最新的数据(a,b的值)发送过去

            try
            
                // 我们定义一个常数,它将表示接收到的数据的大小。 它是由我们建立的,我们可以设定任何值。 我们知道在这种情况下,发送的数据的大小非常小。
                const int maxMessageSize = 2048;
                // received bits的缓冲区

                while (webSocket != null && webSocket.State == WebSocketState.Open)  // 如果连接是打开的
                
                    // 此句放在while里面,每次使用都重新初始化。如果放在外面,由于没有进行清空操作,下一次接收的数据若比上一次短,则会多出一部分内容。
                    var receiveBuffer = new ArraySegment<Byte>(new Byte[maxMessageSize]);

                    WebSocketReceiveResult receiveResult = null;
                    byte[] payloadData = null;
                    do
                    
                        // 读取数据。此类的实例表示在 WebSocket 上执行单个 ReceiveAsync 操作所得到的结果
                        receiveResult = await webSocket.ReceiveAsync(receiveBuffer, CancellationToken.None);
                        // 字节数组
                        payloadData = receiveBuffer.Array.Where(b => b != 0).ToArray();
                    
                    while (!receiveResult.EndOfMessage);  // 如果指示已完整接收消息则停止

                    // 如果输入帧为取消帧,发送close命令。
                    // MessageType指示当前消息是utf-8消息还是二进制信息。Text(0,明文形式),Close(2,收到关闭消息,接受已完成),Binary(1,消息采用二进制格式)
                    if (receiveResult.MessageType == WebSocketMessageType.Close)
                    
                        await webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, String.Empty, CancellationToken.None);
                        _sockets.Remove(webSocket);  // 从列表移除当前连接

                    
                    else
                    
                        // 因为我们知道这是一个字符串,我们转换它                        
                        string receiveString = System.Text.Encoding.UTF8.GetString(payloadData, 0, payloadData.Length);

                        try  // 将反序列化内容放入try中,避免无法匹配、内容为空等可能报错的地方
                        
                            // 将转换后的字符串内容进行json反序列化。参考:https://www.cnblogs.com/yinmu/p/12160343.html
                            TestValue tv = JsonConvert.DeserializeObject<TestValue>(receiveString);
                            // 将收到的a,b的值显示到文本框
                            if (tv != null)
                            
                                string valueA = string.Empty, valueB = string.Empty;
                                if (tv.a != null && tv.a.Length > 0)  valueA = tv.a; 
                                if (tv.a != null && tv.b.Length > 0)  valueB = tv.b; 
                                txtAvalue.Text = valueA;
                                txtBvalue.Text = valueB;
                            

                            RefreshConnectionList();  // 先清理无效的连接,否则会导致服务端websocket被dispose

                            //  当接收到文本消息时,对当前服务器上所有web socket连接进行广播
                            foreach (var innerSocket in _sockets)
                            
                                await innerSocket.SendAsync(new ArraySegment<byte>(payloadData), WebSocketMessageType.Text, true, CancellationToken.None);
                            
                        
                        catch (Exception ex)
                        
                            // 如果json反序列化出了问题
                            txtInfo.AppendText(ex.ToString() + DateTime.Now.ToString() + "\\n");  // 将错误类型显示出来
                            txtInfo.AppendText(receiveString + DateTime.Now.ToString() + "\\n");  // 将收到的原始字符串显示出来
                        
                    
                
            
            catch (Exception e)
            
                if (e.GetType().ToString() == "System.Net.WebSockets.WebSocketException")
                
                    // 客户端关闭时会抛出此错误
                    txtInfo.AppendText("连接已关闭" + DateTime.Now.ToString() + "\\n");
                
                else
                
                    txtInfo.AppendText(e.ToString() + DateTime.Now.ToString() + "\\n");
                
            
        
        #endregion 监听方法

        #region 广播
        /// <summary>
        /// 服务端主动向所有客户端广播
        /// </summary>
        /// <param name="jsonmessage">传过来的应该是序列化后的json字符串,接收方会通过TestValue类进行反序列化获取a,b的内容</param>
        public async void Broadcast(string jsonmessage)
        
            try
            
                Byte[] bytes = System.Text.Encoding.UTF8.GetBytes(jsonmessage);
                RefreshConnectionList();//先清理无效的连接,否则会导致服务端websocket被dispose
                //当接收到文本消息时,对当前服务器上所有web socket连接进行广播
                foreach (var innerSocket in _sockets)
                
                    await innerSocket.SendAsync(new ArraySegment<byte>(bytes), WebSocketMessageType.Text, true, CancellationToken.None);
                
            
            catch (Exception ex)
            
                txtInfo.AppendText(ex.ToString() + DateTime.Now.ToString() + "\\n");
                MessageBox.Show("某些连接出了问题,如果广播多次出问题,请重启服务端");
            
        
        /// <summary>
        /// 监听到一个新的websocket连接后,将服务器当前最新数据同步过去
        /// </summary>
        /// <param name="currentWebsocket">当前新接入的websocket连接</param>
        public async void SendToNewConnection(WebSocket currentWebsocket)
        
            try
            
                string jsonmessage = RequestMsg.SerializeJson(txtAvalue.Text, txtBvalue.Text);
                Byte[] bytes = System.Text.Encoding.UTF8.GetBytes(jsonmessage);

                if (currentWebsocket.State == WebSocketState.Open)
                
                    await currentWebsocket.SendAsync(new ArraySegment<byte>(bytes), WebSocketMessageType.Text, true, CancellationToken.None);//try访问已释放对象问题
                
                else
                
                    //此处并不对该链接进行移除,会导致调用本方法后的代码出问题,只需在进行发送时确认状态即可
                    txtInfo.AppendText("新接入连接:" + currentWebsocket.GetHashCode().ToString() + "的连接状态不为open,因此停止向其同步数据" + DateTime.Now.ToString() + "\\n");
                
            
            catch (Exception ex)
            
                txtInfo.AppendText(ex.ToString() + DateTime.Now.ToString() + "\\n");
            
        

        /// <summary>
        /// 刷新当前websocket连接列表,如果状态为Closed,则移除。连接异常断开后会被dispose,如果访问会报错,但可以获取状态为closed
        /// </summary>
        public static void RefreshConnectionList()
        
            if (_sockets != null)//lock不能锁定空值
            
                lock (_sockets)//锁定数据源
                
                    //System.InvalidOperationException: 集合已修改;可能无法执行枚举操作。
                    //使用foreach不能执行删除、修改,这是规定。你可以使用for循环遍历修改。删除数据正确做法,for循环 i 要从大到小
                    for (int i = _sockets.Count - 1; i >= 0; i--)
                    
                        if (_sockets[i].State != WebSocketState.Open)
                        
                            _sockets.Remove(_sockets[i]);
                        
                    
                
            

        
        #endregion
    

2、WebForm端示例:

WinSocketClent.cshtml (注:Clent->Client

@
    ViewData["Title"] = "WinSocket客户端";
    Layout = null;

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <title>WinSocket客户端</title>
</head>
<body>
    <div>
        <form id="Form">
            <label id="address">服务端地址:</label>
            <input name="" id="IpAddress" value="ws://127.0.0.1:8080" />
            <button type="submit" onclick="Connect();">连接</button><br />

            <label id="a">a</label>
            <input name="" id="ValueA" value="" />
            <button type="submit" onclick="SendData();">提交</button><br />

            <label id="b">b</label>
            <input name="" id="ValueB" value="" />
        </form>
        <div id="txtInfo" ></div>
    </div>
</body>
</html>
@
<script type="text/javascript">
    var test = function () 

        var print = document.getElementById(\'txtInfo\');
        var form = document.getElementById(\'Form\');
        var inputStrA = document.getElementById(\'ValueA\');
        var ipaddress = document.getElementById(\'IpAddress\').value;

        print.innerHTML += "connecting to server ..<br/>";

        //参数即想要连接服务器的ip。 服务器可以是node.js, 也可以是其他项目,如c#
        //window.ws = new WebSocket(\'ws://10.206.14.152:8080/\'); //连接服务
        //window.ws = new WebSocket(\'ws://192.168.43.78:8080/\'); //连接服务
        window.ws = new WebSocket(ipaddress); //连接服务


        //监听消息状态
        ws.onmessage = function (msg) 
            var jsobj = JSON.parse(msg.data);//json字符串转为对象
            document.getElementById(\'ValueA\').value = jsobj.a;//写入输入框中
            document.getElementById(\'ValueB\').value = jsobj.b;

            print.innerHTML += msg.data + \'<br/>\'
        
        //监听链接状态
        ws.onopen = function () 
            print.innerHTML += \'监听 打开 <br/>\'
        
        //监听关闭状态
        ws.onclose = function () 
            print.innerHTML += \'监听 关闭<br/>\';
        

        //向服务器端发送消息
        form.addEventListener(\'submit\', function (e) 
            e.preventDefault();
            //序列化后的字符串发给服务端,服务端以字节数组格式接收,若转成字符串并添加部分信息再转回字节数组时,string.format函数会报错
            //var jsonObj =  "name": "zhangsan", "age": 18 ;
            //传入一个json字符串进行测试,服务器会进行判断。
            //ws.send(JSON.stringify(jsonObj));
            //ws.send(jsonObj);
            //传入一个非json字符串进行测试,服务器会进行判断。
            //ws.send("test");
        )
    
    //window.onload = test();

    function Connect() 
        test();
    

    function SendData() 
        var valueA = document.getElementById(\'ValueA\').value;
        var valueB = document.getElementById(\'ValueB\').value;

        if (valueA.length == 0)  valueA = "-"; 
        if (valueB.length == 0)  valueB = "-"; 

        var jsonobj = 
            "a": valueA,
            "b": valueB
        ;
        var jsonstr = JSON.stringify(jsonobj);

        //初始化WebSocket
        //InitWebSocket();
        //如果WebSocket打开,发送数据
        if (ws.OPEN && ws.readyState == 1) 
            ws.send(jsonstr);
        
        console.log(ws.readyState);
        //如果WebSocket关闭,显示消息
        if (ws.readyState == 2 || ws.readyState == 3) 
            console.log("进来关闭函数了")
            alert("WebSocket关闭了,无法发送数据");
        
    
</script>

 

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