续实例解析SOCKET编程模型之异步通信篇(上) 代码

    创建线程时,将使用采用委托作为其唯一参数的构造函数创建Thread 类的新实例。但线程在调用 Start方法前不会开始执行。调用后,将从由委托引用的方法的第一行开始执行。如下例所示:

    Thread thread=new Thread(new ThreadStart(ThreadProc));

    thread.Start();

    在以下的源码中我们使用了ManualResetEvent 来允许线程通过发信号互相通信。通常,此通信涉及一个线程在其他线程进行之前必须完成的任务。当线程开始一个活动(此活动必须在其他线程进行之前完成)时,它调用 Reset 将 ManualResetEvent 设置为非终止状态。此线程可被视为控制 ManualResetEvent。调用 ManualResetEvent 上的 WaitOne 的线程将阻塞,并等待信号。当控制线程完成活动时,它调用 Set 以发出等待线程可以继续进行的信号。并释放所有等待线程。一旦它被终止,将保持终止状态,直到它被手动重置。即对 WaitOne 的调用将立即返回。可以通过将布尔值传递给构造函数来控制 ManualResetEvent 的初始状态,如果初始状态处于终止状态,为 true;否则为 false。

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Net;
using System.Net.Sockets;
using System.Threading;
using System.Text;
namespace 聊天_socket
{
 /// <summary>
 /// Form1 的摘要说明。
 /// </summary>
 public class Form1 : System.Windows.Forms.Form
 {
  private System.Windows.Forms.StatusBar statusBar1;
  private System.Windows.Forms.Label label1;
  private System.Windows.Forms.Label label2;
  private System.Windows.Forms.Label label3;
  private System.Windows.Forms.Label label4;
  private System.Windows.Forms.RichTextBox rtbReceive;
  private System.Windows.Forms.RichTextBox rtbSend;
  private System.Windows.Forms.TextBox txtServer;
  private System.Windows.Forms.TextBox txtPort;
  private System.Windows.Forms.Button btnListen;
  private System.Windows.Forms.Button btnSend;
  private System.Windows.Forms.Button btnStop;
  private IPAddress hostIPAddress=IPAddress.Parse("127.0.0.1");
  private IPEndPoint Server;
  private Socket listeningSocket;
  private Socket handler;
  private Socket mySocket;
  private static ManualResetEvent Done=new ManualResetEvent(false);
  private const int BufferSize=256;
  private byte[] buffer=new byte[BufferSize];
  string port;
  /// <summary>
  /// 必需的设计器变量。
  /// </summary>
  private System.ComponentModel.Container components = null;

  public Form1()
  {
   //
   // Windows 窗体设计器支持所必需的
   //
   InitializeComponent();

   //
   // TODO: 在 InitializeComponent 调用后添加任何构造函数代码
   //
  }

  /// <summary>
  /// 清理所有正在使用的资源。
  /// </summary>
  protected override void Dispose( bool disposing )
  {
   if( disposing )
   {
    if (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 - 不要使用代码编辑器修改
  /// 此方法的内容。
  /// </summary>
  private void InitializeComponent()
  {
   this.rtbReceive = new System.Windows.Forms.RichTextBox();
   this.rtbSend = new System.Windows.Forms.RichTextBox();
   this.txtServer = new System.Windows.Forms.TextBox();
   this.txtPort = new System.Windows.Forms.TextBox();
   this.statusBar1 = new System.Windows.Forms.StatusBar();
   this.btnListen = new System.Windows.Forms.Button();
   this.btnSend = new System.Windows.Forms.Button();
   this.btnStop = new System.Windows.Forms.Button();
   this.label1 = new System.Windows.Forms.Label();
   this.label2 = new System.Windows.Forms.Label();
   this.label3 = new System.Windows.Forms.Label();
   this.label4 = new System.Windows.Forms.Label();
   this.SuspendLayout();
   //
   // rtbReceive
   //
   this.rtbReceive.Location = new System.Drawing.Point(80, 56);
   this.rtbReceive.Name = "rtbReceive";
   this.rtbReceive.Size = new System.Drawing.Size(264, 96);
   this.rtbReceive.TabIndex = 0;
   this.rtbReceive.Text = "";
   //
   // rtbSend
   //
   this.rtbSend.Location = new System.Drawing.Point(80, 152);
   this.rtbSend.Name = "rtbSend";
   this.rtbSend.Size = new System.Drawing.Size(264, 96);
   this.rtbSend.TabIndex = 1;
   this.rtbSend.Text = "";
   //
   // txtServer
   //
   this.txtServer.Location = new System.Drawing.Point(72, 16);
   this.txtServer.Name = "txtServer";
   this.txtServer.TabIndex = 2;
   this.txtServer.Text = "127.0.0.1";
   //
   // txtPort
   //
   this.txtPort.Location = new System.Drawing.Point(288, 16);
   this.txtPort.Name = "txtPort";
   this.txtPort.Size = new System.Drawing.Size(48, 21);
   this.txtPort.TabIndex = 3;
   this.txtPort.Text = "19811";
   //
   // statusBar1
   //
   this.statusBar1.Location = new System.Drawing.Point(0, 287);
   this.statusBar1.Name = "statusBar1";
   this.statusBar1.ShowPanels = true;
   this.statusBar1.Size = new System.Drawing.Size(360, 22);
   this.statusBar1.TabIndex = 4;
   this.statusBar1.Text = "statusBar1";
   //
   // btnListen
   //
   this.btnListen.Location = new System.Drawing.Point(32, 256);
   this.btnListen.Name = "btnListen";
   this.btnListen.TabIndex = 5;
   this.btnListen.Text = "开始监听";
   this.btnListen.Click += new System.EventHandler(this.btnListen_Click);
   //
   // btnSend
   //
   this.btnSend.Location = new System.Drawing.Point(144, 256);
   this.btnSend.Name = "btnSend";
   this.btnSend.TabIndex = 6;
   this.btnSend.Text = "发送信息";
   this.btnSend.Click += new System.EventHandler(this.btnSend_Click);
   //
   // btnStop
   //
   this.btnStop.Location = new System.Drawing.Point(256, 256);
   this.btnStop.Name = "btnStop";
   this.btnStop.TabIndex = 7;
   this.btnStop.Text = "停止监听";
   this.btnStop.Click += new System.EventHandler(this.btnStop_Click);
   //
   // label1
   //
   this.label1.Location = new System.Drawing.Point(16, 16);
   this.label1.Name = "label1";
   this.label1.Size = new System.Drawing.Size(56, 23);
   this.label1.TabIndex = 8;
   this.label1.Text = "服务器:";
   //
   // label2
   //
   this.label2.Location = new System.Drawing.Point(216, 16);
   this.label2.Name = "label2";
   this.label2.Size = new System.Drawing.Size(64, 23);
   this.label2.TabIndex = 9;
   this.label2.Text = "监听端口:";
   //
   // label3
   //
   this.label3.Location = new System.Drawing.Point(16, 64);
   this.label3.Name = "label3";
   this.label3.Size = new System.Drawing.Size(64, 23);
   this.label3.TabIndex = 10;
   this.label3.Text = "接收信息:";
   //
   // label4
   //
   this.label4.Location = new System.Drawing.Point(16, 152);
   this.label4.Name = "label4";
   this.label4.Size = new System.Drawing.Size(64, 23);
   this.label4.TabIndex = 11;
   this.label4.Text = "发送信息:";
   //
   // Form1
   //
   this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
   this.ClientSize = new System.Drawing.Size(360, 309);
   this.Controls.Add(this.label4);
   this.Controls.Add(this.label3);
   this.Controls.Add(this.label2);
   this.Controls.Add(this.label1);
   this.Controls.Add(this.btnStop);
   this.Controls.Add(this.btnSend);
   this.Controls.Add(this.btnListen);
   this.Controls.Add(this.statusBar1);
   this.Controls.Add(this.txtPort);
   this.Controls.Add(this.txtServer);
   this.Controls.Add(this.rtbSend);
   this.Controls.Add(this.rtbReceive);
   this.Name = "Form1";
   this.Text = "聊天程序-服务器";
   this.TopMost = true;
   this.Closing += new System.ComponentModel.CancelEventHandler(this.Form1_Closing);
   this.ResumeLayout(false);

  }
  #endregion

  /// <summary>
  /// 应用程序的主入口点。
  /// </summary>
  [STAThread]
  static void Main()
  {
   Application.Run(new Form1());
  }

  private void btnListen_Click(object sender, System.EventArgs e)
  {
   try
   {
    hostIPAddress=IPAddress.Parse(txtServer.Text);
    port=txtPort.Text;
   }
   catch{MessageBox.Show("请输入正确的IP地址格式");}
   try
   {  //通过组合服务的主机 IP 地址和端口号,IPEndPoint 类形成到服务的连接点。
    Server=new IPEndPoint(hostIPAddress,Int32.Parse(port));
    // Create a socket object to establish a connection with the server
    listeningSocket=new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);
    listeningSocket.Bind(Server); //绑定该主机端口
    listeningSocket.Listen(50); //监听端口,等待客户端连接请求。50是队列中最多可容纳的等待接受的传入连接数
    statusBar1.Text="主机"+txtServer.Text+"端口"+txtPort.Text+"开始监听.....";
    //Accept 以同步方式从侦听套接字的连接请求队列中提取第一个挂起的连接请求,然后创建并返回新的 Socket。
    //mySocket=listeningSocket.Accept();
    //一个进程可以创建一个或多个线程以执行与该进程关联的部分程序代码。使用 ThreadStart 委托指定由线程执行的程序代码。
    Thread thread=new Thread(new ThreadStart(ThreadProc));
    thread.Start();
   }
   catch(Exception ee){statusBar1.Text=ee.Message;}
  }
  private void ThreadProc()
  {
   //if(mySocket.Connected)
   //{
    //statusBar1.Text="与客户建立连接.";
    while(true)
    {
     /*Byte[] ByteRecv=new Byte[256];
     mySocket.Receive(ByteRecv,ByteRecv.Length,0);
     string strRecv=Encoding.BigEndianUnicode.GetString(ByteRecv);
     rtbReceive.AppendText(strRecv+"\r\n");*/
     Done.Reset(); //将状态设为非终止
     listeningSocket.BeginAccept(new AsyncCallback(AcceptCallBack),listeningSocket);//开始一个异步操作来接受一个传入的连接尝试
     Done.WaitOne(); //阻塞当前线程,直到当前线程收到信号。
    }
   //}
  }
  private void AcceptCallBack(IAsyncResult ar)//ar表示异步操作的状态。
  {
   Done.Set();//设为终止
   mySocket=(Socket)ar.AsyncState; //获取状态
   handler=mySocket.EndAccept(ar);   //异步接受传入的连接尝试,并创建新的 Socket 来处理远程主机通信,获取结果
   try
   {
    byte[] byteData=Encoding.BigEndianUnicode.GetBytes("准备完毕,可以通话"+"\r\n");
    //调用SendCallBack异步发送数据,
    handler.BeginSend(byteData,0,byteData.Length,0,new AsyncCallback(SendCallBack),handler);
   }
   catch(Exception ee){MessageBox.Show(ee.Message);}
   Thread thread=new Thread(new ThreadStart(ThreadRev));
   thread.Start();
  }
  
  private void SendCallBack(IAsyncResult ar)
  {
   try
   {
    handler=(Socket)ar.AsyncState;  //获取状态
    int bytesSent=handler.EndSend(ar);//结束挂起的异步发送,返回向 Socket 发送的字节数
   }
   catch{}
  }
  private void ThreadRev()
  { 
   handler.BeginReceive(buffer,0,BufferSize,0,new AsyncCallback(ReadCallBack),handler);
  }
  
  private void ReadCallBack(IAsyncResult ar)
  {
   int bytesRead=handler.EndReceive(ar); //结束挂起的异步读取,返回接收到的字节数。
   StringBuilder sb=new StringBuilder();   //接收数据的可变字符字符串,在通过追加、移除、替换或插入字符而创建它后可以对它进行修改。
   sb.Append(Encoding.BigEndianUnicode.GetString(buffer,0,bytesRead));//追加字符串
   string content=sb.ToString();   //转换为字符串
   sb.Remove(0,content.Length);   //清除sb内容
   rtbReceive.AppendText(content+"\r\n");
   handler.BeginReceive(buffer,0,BufferSize,0,new AsyncCallback(ReadCallBack),handler);
  }
  private void btnStop_Click(object sender, System.EventArgs e)
  {
   try
   {
    listeningSocket.Close();
    statusBar1.Text="主机"+txtServer.Text+"端口"+txtPort.Text+"监听停止";
   }
   catch{MessageBox.Show("监听尚未开始,关闭无效");}
  }

  private void btnSend_Click(object sender, System.EventArgs e)
  {
   try
   {
    string strSend ="Server--->"+rtbSend.Text+"\r\n";
    Byte[] ByteSend = Encoding.BigEndianUnicode.GetBytes(strSend);
    handler.BeginSend(ByteSend,0,ByteSend.Length,0,new AsyncCallback(SendCallBack),handler);
   }
   catch{MessageBox.Show("连接尚未建立,无法发送.");}
  }

  private void Form1_Closing(object sender, System.ComponentModel.CancelEventArgs e)
  {
   try
   {
    listeningSocket.Close();//在窗口关闭之前关闭Scoket连接并释放所有关联的资源。
   }
   catch{}
  }
 }
}

原文地址:https://www.cnblogs.com/gfwei/p/895226.html