异步 TCP 通信 ---- AsyncTcpClient

using System;
using System.Diagnostics;
using System.Globalization;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;

namespace JCommon.Network
{
    /// <summary>
    /// 异步 TCP 客户端
    /// </summary>
    public class AsyncTcpClient : IDisposable
    {
        public event EventHandler<TcpDatagramReceivedEventArgs<byte[]>> DatagramReceived;       // 接收到数据报文事件
        public event EventHandler<TcpDatagramReceivedEventArgs<string>> PlaintextReceived;      // 接收到数据报文明文事件
        public event EventHandler<TcpServerConnectedEventArgs> ServerConnected;                 // 与服务器的连接已建立事件
        public event EventHandler<TcpServerDisconnectedEventArgs> ServerDisconnected;           // 与服务器的连接已断开事件
        public event EventHandler<TcpServerExceptionOccurredEventArgs> ServerExceptionOccurred; // 与服务器的连接发生异常事件
        
        private TcpClient tcpClient;
        private bool disposed = false;
        private int retries = 0;        // 重连计数
       
        public AsyncTcpClient(IPAddress remoteIPAddress, int remotePort)
        {
            this.Addresses = remoteIPAddress;
            this.Port = remotePort;
            this.Encoding = Encoding.Default;
            this.Retries = 3;
            this.RetryInterval = 5;
        }

        /// <summary>
        /// 是否已与服务器建立连接
        /// </summary>
        public bool Connected
        {
            get
            {
                return this.tcpClient.Client.Connected;
            }
        }

        /// <summary>
        /// 远端服务器的IP地址列表
        /// </summary>
        public IPAddress Addresses { get; private set; }

        /// <summary>
        /// 远端服务器的端口
        /// </summary>
        public int Port { get; private set; }

        /// <summary>
        /// 连接重试次数
        /// </summary>
        public int Retries { get; set; }

        /// <summary>
        /// 连接重试间隔
        /// </summary>
        public int RetryInterval { get; set; }

        /// <summary>
        /// 远端服务器终结点
        /// </summary>
        public IPEndPoint RemoteIPEndPoint
        {
            get
            {
                return new IPEndPoint(this.Addresses, this.Port);
            }
        }

        /// <summary>
        /// 通信所使用的编码
        /// </summary>
        public Encoding Encoding { get; set; }

        /// <summary>
        /// 连接到服务器
        /// </summary>
        /// <returns></returns>
        public AsyncTcpClient Connect()
        {
            this.tcpClient = new TcpClient();
            if (!this.Connected)
            {
                this.tcpClient.BeginConnect(this.Addresses, this.Port, new AsyncCallback(this.HandleTcpServerConnected), this.tcpClient);
            }
            return this;
        }

        /// <summary>
        /// 关闭与服务器的连接
        /// </summary>
        /// <returns>异步TCP客户端</returns>
        public AsyncTcpClient Close()
        {
            if (this.Connected)
            {
                this.retries = 0;
                this.tcpClient.Close();
                this.RaiseServerDisconnected(this.Addresses, this.Port);
            }
            return this;
        }

        private void HandleTcpServerConnected(IAsyncResult ar)
        {
            try
            {
                this.tcpClient.EndConnect(ar);
                this.RaiseServerConnected(this.Addresses, this.Port);
                this.retries = 0;
            }
            catch (Exception ex)
            {
                // 限制重连次数
                if (this.Retries > 0)
                {
                    if (this.retries > 0)
                    {
                        Trace.WriteLine(string.Format(CultureInfo.InvariantCulture, "Connect to server with retry {0} failed.", retries));
                    }

                    this.retries++;
                    if (this.retries > this.Retries)
                    {
                        this.RaiseServerExceptionOccurred(this.Addresses, this.Port, ex);
                        return;
                    }
                }
                
                Thread.Sleep(TimeSpan.FromSeconds((double)this.RetryInterval));
                this.Connect();
                return;
            }
            byte[] buffer = new byte[this.tcpClient.ReceiveBufferSize];
            this.tcpClient.GetStream().BeginRead(buffer, 0, buffer.Length, new AsyncCallback(this.HandleDatagramReceived), buffer);
        }

        private void HandleDatagramReceived(IAsyncResult ar)
        {
            try
            {
                NetworkStream stream = this.tcpClient.GetStream();
                int numberOfReadBytes = 0;
                try
                {
                    numberOfReadBytes = stream.EndRead(ar);
                }
                catch
                {
                    numberOfReadBytes = 0;
                }
                if (numberOfReadBytes == 0)
                {
                    this.Close();
                    
                    // 断开重连可写在这里
                    Trace.WriteLine("连接断开,尝试重连...");
                    this.Connect();
                }
                else
                {
                    byte[] buffer = (byte[])ar.AsyncState;
                    byte[] receivedBytes = new byte[numberOfReadBytes];
                    Buffer.BlockCopy(buffer, 0, receivedBytes, 0, numberOfReadBytes);
                    this.RaiseDatagramReceived(this.tcpClient, receivedBytes);
                    this.RaisePlaintextReceived(this.tcpClient, receivedBytes);

                    // then start reading from the network again
                    stream.BeginRead(buffer, 0, buffer.Length, new AsyncCallback(this.HandleDatagramReceived), buffer);
                }
            }
            catch(Exception ex)
            {
                Trace.WriteLine(ex.Message);
            }
        }

        private void RaiseDatagramReceived(TcpClient sender, byte[] datagram)
        {
            if (this.DatagramReceived != null)
            {
                this.DatagramReceived(this, new TcpDatagramReceivedEventArgs<byte[]>(sender, datagram));
            }
        }

        private void RaisePlaintextReceived(TcpClient sender, byte[] datagram)
        {
            if (this.PlaintextReceived != null)
            {
                this.PlaintextReceived(this, new TcpDatagramReceivedEventArgs<string>(sender, this.Encoding.GetString(datagram, 0, datagram.Length)));
            }
        }

        private void RaiseServerConnected(IPAddress ipAddresses, int port)
        {
            if (this.ServerConnected != null)
            {
                this.ServerConnected(this, new TcpServerConnectedEventArgs(ipAddresses, port));
            }
        }

        private void RaiseServerDisconnected(IPAddress ipAddresses, int port)
        {
            if (this.ServerDisconnected != null)
            {
                this.ServerDisconnected(this, new TcpServerDisconnectedEventArgs(ipAddresses, port));
            }
        }

        private void RaiseServerExceptionOccurred(IPAddress ipAddresses, int port, Exception innerException)
        {
            if (this.ServerExceptionOccurred != null)
            {
                this.ServerExceptionOccurred(this, new TcpServerExceptionOccurredEventArgs(ipAddresses, port, innerException));
            }
        }

        /// <summary>
        /// 发送报文
        /// </summary>
        /// <param name="datagram"></param>
        public void Send(byte[] datagram)
        {
            if (datagram == null)
            {
                throw new ArgumentNullException("datagram");
            }
            if (!this.Connected)
            {
                this.RaiseServerDisconnected(this.Addresses, this.Port);
                throw new InvalidProgramException("This client has not connected to server.");
            }
            this.tcpClient.GetStream().BeginWrite(datagram, 0, datagram.Length, new AsyncCallback(this.HandleDatagramWritten), this.tcpClient);
        }

        private void HandleDatagramWritten(IAsyncResult ar)
        {
            ((TcpClient)ar.AsyncState).GetStream().EndWrite(ar);
        }

        public void Send(string datagram)
        {
            this.Send(this.Encoding.GetBytes(datagram));
        }

        /// <summary>
        /// 释放非托管资源
        /// </summary>
        public void Dispose()
        {
            this.Dispose(true);
            GC.SuppressFinalize(this);
        }

        protected virtual void Dispose(bool disposing)
        {
            if (!this.disposed)
            {
                if (disposing)
                {
                    try
                    {
                        this.Close();
                        if (this.tcpClient != null)
                        {
                            this.tcpClient = null;
                        }
                    }
                    catch// (SocketException ex)
                    {
                    }
                }
                this.disposed = true;
            }
        }
    }
}

using System;
using System.Net.Sockets;

namespace JCommon.Network
{
    /// <summary>
    /// 接收到数据报文事件
    /// </summary>
    /// <typeparam name="T"></typeparam>
    public class TcpDatagramReceivedEventArgs<T> : EventArgs
    {
        public TcpDatagramReceivedEventArgs(TcpClient tcpClient, T datagram)
        {
            this.TcpClient = tcpClient;
            this.Datagram = datagram;
        }

        public TcpClient TcpClient { get; private set; }

        public T Datagram { get; private set; }
    }
}

using System;
using System.Net.Sockets;

namespace JCommon.Network
{
    /// <summary>
    /// 接收到数据报文事件
    /// </summary>
    /// <typeparam name="T"></typeparam>
    public class TcpDatagramReceivedEventArgs<T> : EventArgs
    {
        public TcpDatagramReceivedEventArgs(TcpClient tcpClient, T datagram)
        {
            this.TcpClient = tcpClient;
            this.Datagram = datagram;
        }

        public TcpClient TcpClient { get; private set; }

        public T Datagram { get; private set; }
    }
}

using System;
using System.Globalization;
using System.Net;

namespace JCommon.Network
{
    /// <summary>
    /// 与服务器的连接已建立事件
    /// </summary>
    public class TcpServerConnectedEventArgs : EventArgs
    {
        public TcpServerConnectedEventArgs(IPAddress ipAddress, int port)
        {
            if (ipAddress == null)
            {
                throw new ArgumentNullException("ipAddress");
            }
            this.Address = ipAddress;
            this.Port = port;
        }

        public IPAddress Address { get; private set; }

        public int Port { get; private set; }

        public override string ToString()
        {
            return this.Address + ":" + this.Port.ToString(CultureInfo.InvariantCulture);
        }
    }
}

using System;
using System.Globalization;
using System.Net;

namespace JCommon.Network
{
    /// <summary>
    /// 与服务器的连接已断开事件
    /// </summary>
    public class TcpServerDisconnectedEventArgs : EventArgs
    {
        public TcpServerDisconnectedEventArgs(IPAddress ipAddress, int port)
        {
            if (ipAddress == null)
            {
                throw new ArgumentNullException("ipAddress");
            }
            this.Address = ipAddress;
            this.Port = port;
        }

        public IPAddress Address { get; private set; }

        public int Port { get; private set; }

        public override string ToString()
        {
            return this.Address + ":" + this.Port.ToString(CultureInfo.InvariantCulture);
        }
    }
}

using System;
using System.Globalization;
using System.Net;

namespace JCommon.Network
{
    /// <summary>
    /// 与服务器的连接发生异常事件
    /// </summary>
    public class TcpServerExceptionOccurredEventArgs : EventArgs
    {
        public TcpServerExceptionOccurredEventArgs(IPAddress ipAddresses, int port, Exception innerException)
        {
            if (ipAddresses == null)
            {
                throw new ArgumentNullException("ipAddress");
            }
            this.Address = ipAddresses;
            this.Port = port;
            this.Exception = innerException;
        }

        public IPAddress Address { get; private set; }

        public int Port { get; private set; }

        public Exception Exception { get; private set; }

        public override string ToString()
        {
            return this.Address + ":" + this.Port.ToString(CultureInfo.InvariantCulture);
        }
    }
}

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 JCommon.Network;
using System.Net;

namespace JCommon.Test
{
    public partial class FrmTcpClient_aync : Form
    {
        Network.AsyncTcpClient client = null;


        DelMsgShow msgShow;

        void MsgShow(string str)
        {
            if (richTextBox1.InvokeRequired)
            {
                richTextBox1.Invoke(new Action<string>(MsgShow), new object[] { str });
            }
            else
            {
                richTextBox1.AppendText(str);
                richTextBox1.AppendText("
");
                richTextBox1.ScrollToCaret();
            }
        }


        public FrmTcpClient_aync()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string strServerIP = textBox1.Text;
            int nPort = textBox2.Text.ToInt();

            button1.Enabled = false;
            if(this.client == null)
            {
                IPEndPoint ip = new IPEndPoint(IPAddress.Parse(strServerIP), nPort);
                this.client = new AsyncTcpClient(IPAddress.Parse(strServerIP), nPort);

                this.client.PlaintextReceived += this.onPlaintextReceived;
                this.client.ServerConnected += this.onServerConnected;
                this.client.ServerDisconnected += this.onServerDisconnected;
            }

            string str = button1.Text;
            if (str == "连接")
            {
                this.client.Connect();
                button1.Text = "断开连接";
            }
            else
            {
                this.client.Close();
                button1.Text = "连接";
            }

            button1.Enabled = true;
        }

        private void button2_Click(object sender, EventArgs e)
        {
            string str = richTextBox2.Text;
            if (this.client.Connected)
                this.client.Send(str);
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void onPlaintextReceived(object sender, TcpDatagramReceivedEventArgs<string> e)
        {
            string data = e.Datagram;
            msgShow("收到：" + data);
        }

        public void onServerConnected(object sender, TcpServerConnectedEventArgs e)
        {
            msgShow(this.Name + "连接成功");
        }

        public void onServerDisconnected(object sender, TcpServerDisconnectedEventArgs e)
        {
            msgShow(this.Name + "连接断开");
        }

        private void FrmTcpClient_aync_Load(object sender, EventArgs e)
        {
            msgShow = this.MsgShow;
            this.textBox1.Text = "127.0.0.1";
            this.textBox2.Text = "20000";
        }
    }
}

namespace JCommon.Test
{
    partial class FrmTcpClient_aync
    {
        /// <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()
        {
            this.richTextBox2 = new System.Windows.Forms.RichTextBox();
            this.richTextBox1 = new System.Windows.Forms.RichTextBox();
            this.button2 = new System.Windows.Forms.Button();
            this.button1 = new System.Windows.Forms.Button();
            this.textBox2 = new System.Windows.Forms.TextBox();
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.label2 = new System.Windows.Forms.Label();
            this.label1 = new System.Windows.Forms.Label();
            this.SuspendLayout();
            // 
            // richTextBox2
            // 
            this.richTextBox2.Location = new System.Drawing.Point(32, 234);
            this.richTextBox2.Name = "richTextBox2";
            this.richTextBox2.Size = new System.Drawing.Size(306, 51);
            this.richTextBox2.TabIndex = 4;
            this.richTextBox2.Text = "";
            // 
            // richTextBox1
            // 
            this.richTextBox1.Location = new System.Drawing.Point(29, 65);
            this.richTextBox1.Name = "richTextBox1";
            this.richTextBox1.Size = new System.Drawing.Size(385, 155);
            this.richTextBox1.TabIndex = 3;
            this.richTextBox1.Text = "";
            // 
            // button2
            // 
            this.button2.Location = new System.Drawing.Point(344, 234);
            this.button2.Name = "button2";
            this.button2.Size = new System.Drawing.Size(70, 51);
            this.button2.TabIndex = 5;
            this.button2.Text = "发送";
            this.button2.UseVisualStyleBackColor = true;
            this.button2.Click += new System.EventHandler(this.button2_Click);
            // 
            // button1
            // 
            this.button1.Location = new System.Drawing.Point(320, 19);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(75, 23);
            this.button1.TabIndex = 2;
            this.button1.Text = "连接";
            this.button1.UseVisualStyleBackColor = true;
            this.button1.Click += new System.EventHandler(this.button1_Click);
            // 
            // textBox2
            // 
            this.textBox2.Location = new System.Drawing.Point(214, 21);
            this.textBox2.Name = "textBox2";
            this.textBox2.Size = new System.Drawing.Size(84, 21);
            this.textBox2.TabIndex = 1;
            // 
            // textBox1
            // 
            this.textBox1.Location = new System.Drawing.Point(71, 21);
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(84, 21);
            this.textBox1.TabIndex = 0;
            // 
            // label2
            // 
            this.label2.AutoSize = true;
            this.label2.Location = new System.Drawing.Point(179, 24);
            this.label2.Name = "label2";
            this.label2.Size = new System.Drawing.Size(29, 12);
            this.label2.TabIndex = 7;
            this.label2.Text = "Port";
            // 
            // label1
            // 
            this.label1.AutoSize = true;
            this.label1.Location = new System.Drawing.Point(37, 24);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(17, 12);
            this.label1.TabIndex = 6;
            this.label1.Text = "IP";
            // 
            // FrmTcpClient_aync
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(456, 311);
            this.Controls.Add(this.richTextBox2);
            this.Controls.Add(this.richTextBox1);
            this.Controls.Add(this.button2);
            this.Controls.Add(this.button1);
            this.Controls.Add(this.textBox2);
            this.Controls.Add(this.textBox1);
            this.Controls.Add(this.label2);
            this.Controls.Add(this.label1);
            this.Name = "FrmTcpClient_aync";
            this.Text = "FrmTcpClient_aync";
            this.Load += new System.EventHandler(this.FrmTcpClient_aync_Load);
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private System.Windows.Forms.RichTextBox richTextBox2;
        private System.Windows.Forms.RichTextBox richTextBox1;
        private System.Windows.Forms.Button button2;
        private System.Windows.Forms.Button button1;
        private System.Windows.Forms.TextBox textBox2;
        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.Label label2;
        private System.Windows.Forms.Label label1;
    }
}