C#WPF上位机实现和下位机TCP通讯的方法

下位机使用北京大华程控电源DH1766-1，上位机使用WPF。实现了电压电流实时采集，曲线显示。上午在公司调试成功，手头没有程控电源，使用TCP服务端模拟。昨天写的TCP服务端正好排上用场。

界面如下：

服务端

服务端实在上篇基础上实现的。需要做如下更改：

while (true)
             {
               try
               {
                 byte[] bufferDate = new byte[1024];
                 int realLen = pSocket.Receive(bufferDate);
                 if (realLen <= 0)
                 {
                   this.Invoke(addTextDelegate, pSocket.RemoteEndPoint.ToString() + "退出\r\n");
                   socketList.Remove(pSocket);
                   //客户端退出的时候会发送一个空字节
                   pSocket.Shutdown(SocketShutdown.Both);
                   pSocket.Close();
                   return;
                 }
                 string receiveStr = Encoding.Default.GetString(bufferDate, 0, realLen);
                 switch (receiveStr)
                 {
                   case "MEAS:VOLTage:ALL?\n":
                     proxSocket.Send(Encoding.Default.GetBytes(r.Next(16,25).ToString()+ ","+r.Next(16, 25).ToString()+","+ r.Next(16, 25).ToString()));
                     break;
                   case "MEAS:CURR:ALL?\n":
                     proxSocket.Send(Encoding.Default.GetBytes(r.Next(2, 5).ToString() + "," + r.Next(2, 5).ToString() + "," + r.Next(2, 5).ToString()));
                     break;
                   default:
                     break;
                 }
                 this.Invoke(addTextDelegate, receiveStr + "from" + pSocket.RemoteEndPoint.ToString() + "\r\n");
               }
               catch (Exception ex)
               {
                 this.Invoke(addTextDelegate, pSocket.RemoteEndPoint.ToString() + "异常退出\r\n");
                 socketList.Remove(pSocket);
                 pSocket.Shutdown(SocketShutdown.Both);
                 pSocket.Close();
                 return;
               }
             }

在While循环中加入：

switch (receiveStr)
{
　　case "MEAS:VOLTage:ALL?\n":
　　proxSocket.Send(Encoding.Default.GetBytes(r.Next(16,25).ToString()+ ","+r.Next(16, 25).ToString()+","+ r.Next(16, 25).ToString()));
　　break;
　　case "MEAS:CURR:ALL?\n":
　　proxSocket.Send(Encoding.Default.GetBytes(r.Next(2, 5).ToString() + "," + r.Next(2, 5).ToString() + "," + r.Next(2, 5).ToString()));
　　break;
　　default:
　　break;
}

模拟电源，当收到电压查询时，发送16~25中随机数，由于电源是三个通道的，因此发送三个随机数，用逗号隔开。同样收到电流查询，发送2~5之间的随机数。

完整的客户端源码：

public partial class Form1 : Form
  {
    public Form1()
    {
      InitializeComponent();
      addTextDelegate = new AddTextDelegate(AddText);
    }
    private AddTextDelegate addTextDelegate;
    private List socketList = new List();

    public delegate void AddTextDelegate(string text);
    private void AddText(string text)
    {
      txtLog.Text += text;
    }

    Random r = new Random();

    private void btnStart_Click(object sender, EventArgs e)
    {
      //参数：寻址方式  传输数据方式 通信协议
      Socket socket = new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);

      IPAddress iPAddress = IPAddress.Parse(txtIP.Text);

      //创建EndPoint
      IPEndPoint iPEndPoint = new IPEndPoint(iPAddress, int.Parse(txtPort.Text));

      //绑定端口
      socket.Bind(iPEndPoint);

      //开启侦听
      socket.Listen(10);

      txtLog.Text += "服务启动开启侦听……\r\n";

      Thread thread = new Thread((s) =>
       {
         Socket serSocket = (Socket)s;
         while (true)//不断接收客户端连接
         {
           this.Invoke(addTextDelegate, "服务正在等待客户端连接……\r\n");

           //开始接收客户端的连接
           //阻塞当前线程，等待客户端连接
           //客户端连接上之后，服务端自动生成一个socket和连接的客端通信
           Socket proxSocket = serSocket.Accept();

           this.Invoke(addTextDelegate, "客户端连接成功！\r\n" + proxSocket.RemoteEndPoint.ToString());

           //proxSocket.Send(Encoding.Default.GetBytes("连接成功！"));

           socketList.Add(proxSocket);//当前通信的socket放到集合中

           new Thread(p =>
           {
             Socket pSocket = (Socket)p;
             while (true)
             {
               try
               {
                 byte[] bufferDate = new byte[1024];
                 int realLen = pSocket.Receive(bufferDate);

                 if (realLen <= 0)
                 {
                   this.Invoke(addTextDelegate, pSocket.RemoteEndPoint.ToString() + "退出\r\n");

                   socketList.Remove(pSocket);
                   //客户端退出的时候会发送一个空字节
                   pSocket.Shutdown(SocketShutdown.Both);
                   pSocket.Close();

                   return;
                 }
                 string receiveStr = Encoding.Default.GetString(bufferDate, 0, realLen);
                 switch (receiveStr)
                 {
                   case "MEAS:VOLTage:ALL?\n":
                     proxSocket.Send(Encoding.Default.GetBytes(r.Next(16,25).ToString()+ ","+r.Next(16, 25).ToString()+","+ r.Next(16, 25).ToString()));
                     break;
                   case "MEAS:CURR:ALL?\n":
                     proxSocket.Send(Encoding.Default.GetBytes(r.Next(2, 5).ToString() + "," + r.Next(2, 5).ToString() + "," + r.Next(2, 5).ToString()));
                     break;
                   default:
                     break;
                 }
                 this.Invoke(addTextDelegate, receiveStr + "from" + pSocket.RemoteEndPoint.ToString() + "\r\n");
               }
               catch (Exception ex)
               {
                 this.Invoke(addTextDelegate, pSocket.RemoteEndPoint.ToString() + "异常退出\r\n");

                 socketList.Remove(pSocket);
                 pSocket.Shutdown(SocketShutdown.Both);
                 pSocket.Close();
                 return;
               }
             }
           })
           { IsBackground = true }.Start(proxSocket);
         }
       });
      thread.IsBackground = true;
      thread.Start(socket);
      
    }

    private void btnSend_Click(object sender, EventArgs e)
    {
      string str = txtSend.Text;
      byte[] data = Encoding.Default.GetBytes(str);
      foreach (var socket in socketList)
      {
        if (socket != null && socket.Connected)
        {
          socket.Send(data);
        }
      }
    }
  }

上位机实现客户端功能。具体如下：

1、字段和属性

public readonly IPEndPoint TagetIPEP;

public bool IsConnected { get; set; } = false;

private Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp) { /*ReceiveTimeout=1000,SendTimeout=1000*/};

private Thread recListenThread;

public string ReceiveStr { get; set; }

public byte[] ReceiveByte { get; set; }

TagetIPEP是服务器地址和端口。

IsConnected是连接的状态，这个比较重要，在发送和接收时，都要更加IsConnected进行，并更新IsConnected。

Socket用于和客户端通讯。

recListenThread是监听客户端消息的线程。

ReceiveStr和ReceiveByte用来存储客户端发来的消息。

2、方法函数连接方法：

public bool Connect()
    {
      try
      {
        socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
        {
          //ReceiveTimeout = 1000,
          //SendTimeout=1000
        };

        //IAsyncResult cOnnResult= socket.BeginConnect(TagetIPEP.Address, TagetIPEP.Port, null, null);
        //connResult.AsyncWaitHandle.WaitOne(5000, true);
        //if (connResult.IsCompleted)
        //{
        socket.Connect(TagetIPEP.Address, TagetIPEP.Port);
        IsCOnnected= true;
          //开启接收监听

          recListenThread = new Thread(() =>
          {
            while (true)
            {
              try
              {
                ReceiveByte = new byte[1024];
                int realLen = socket.Receive(ReceiveByte);
                ReceiveStr = Encoding.Default.GetString(ReceiveByte, 0, realLen);
                ReceiveEvent();
                if (realLen <= 0)
                {
                  if (socket != null && socket.Connected)
                  {
                    //服务器退出
                    IsCOnnected= false;
                    Log.WriteLog("服务器退出！");
                    socket.Shutdown(SocketShutdown.Both);
                    socket.Close();
                    MessageBox.Show("连接断开！");
                  }
                  return;
                }
              }
              catch (Exception ex)
              {
                if (socket != null && socket.Connected)
                {
                  IsCOnnected= false;
                  Log.WriteLog("服务器异常退出！", ex);
                  socket.Shutdown(SocketShutdown.Both);
                  socket.Close();
                }
                return;
              }
            }
          })
          { IsBackground = true };
          recListenThread.Start();
          return true;
        //}

      }
      catch (Exception ex)
      {
        Log.WriteLog(TagetIPEP.Address + "连接失败", ex);
      }
      return false;
    }

连接函数返回值为bool类型，根据返回值判断连接是否成功连接。这里每次连接都实例化了一个socket，因为在执行socket.close()后，重新打开会失败，而断线重连会经常用到，没有找到更好的方法，干脆重新实例化socket。连接成功后，开启监听服务端消息的线程。这里使用了一个ReceiveEvent()事件，在接收到消息时会触发这个事件，刷新UI界面。

发送方法：

public bool Send(string msg)
    {
      byte[] sendMsg = Encoding.Default.GetBytes(msg);
      if (sendMsg.Length > 0&&IsConnected)
      {
        if (socket != null && socket.Connected)
        {
          try
          {
            socket.Send(sendMsg);
            return true;
          }
          catch (Exception ex)
          {
            IsCOnnected= false;
            Log.WriteLog("发送数据失败,目标地址" + TagetIPEP.Address, ex);
          }
        }
      }

      return false;

    }

关闭方法：

public void Close()
    {
      if (socket != null && socket.Connected)
      {
        IsCOnnected= false;
        recListenThread.Abort();
        Log.WriteLog("关闭连接！");
        socket.Shutdown(SocketShutdown.Both);
        socket.Close();
      }
    }

在出现异常时调用

消息接收事件：

public event Action ReceiveEvent;

每次接收消息时触发，获取属性ReceiveStr和ReceiveByte的值，刷新UI界面。

完整代码：

public class TCPClient
  {
    public TCPClient(/*IPEndPoint localIPEP,*/IPEndPoint targetIPEP)
    {
      //socket.Bind(localIPEP);
      TagetIPEP = targetIPEP;
      
    }

    public readonly IPEndPoint TagetIPEP;

    public bool IsConnected { get; set; } = false;

    private Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp) { /*ReceiveTimeout=1000,SendTimeout=1000*/};

    public bool Connect()
    {
      try
      {
        socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
        {
          //ReceiveTimeout = 1000,
          //SendTimeout=1000
        };

        //IAsyncResult cOnnResult= socket.BeginConnect(TagetIPEP.Address, TagetIPEP.Port, null, null);
        //connResult.AsyncWaitHandle.WaitOne(5000, true);
        //if (connResult.IsCompleted)
        //{
        socket.Connect(TagetIPEP.Address, TagetIPEP.Port);
        IsCOnnected= true;
          //开启接收监听

          recListenThread = new Thread(() =>
          {
            while (true)
            {
              try
              {
                ReceiveByte = new byte[1024];
                int realLen = socket.Receive(ReceiveByte);
                ReceiveStr = Encoding.Default.GetString(ReceiveByte, 0, realLen);
                ReceiveEvent();
                if (realLen <= 0)
                {
                  if (socket != null && socket.Connected)
                  {
                    //服务器退出
                    IsCOnnected= false;
                    Log.WriteLog("服务器退出！");
                    socket.Shutdown(SocketShutdown.Both);
                    socket.Close();
                    MessageBox.Show("连接断开！");
                  }
                  return;
                }
              }
              catch (Exception ex)
              {
                if (socket != null && socket.Connected)
                {
                  IsCOnnected= false;
                  Log.WriteLog("服务器异常退出！", ex);
                  socket.Shutdown(SocketShutdown.Both);
                  socket.Close();
                }
                return;
              }
            }
          })
          { IsBackground = true };
          recListenThread.Start();
          return true;
        //}

      }
      catch (Exception ex)
      {
        Log.WriteLog(TagetIPEP.Address + "连接失败", ex);
      }
      return false;
    }

    public bool Send(string msg)
    {
      byte[] sendMsg = Encoding.Default.GetBytes(msg);
      if (sendMsg.Length > 0&&IsConnected)
      {
        if (socket != null && socket.Connected)
        {
          try
          {
            socket.Send(sendMsg);
            return true;
          }
          catch (Exception ex)
          {
            IsCOnnected= false;
            Log.WriteLog("发送数据失败,目标地址" + TagetIPEP.Address, ex);
          }
        }
      }

      return false;

    }

    public event Action ReceiveEvent;

    public string ReceiveStr { get; set; }

    public byte[] ReceiveByte { get; set; }

    public void Close()
    {
      if (socket != null && socket.Connected)
      {
        IsCOnnected= false;
        recListenThread.Abort();
        Log.WriteLog("关闭连接！");
        socket.Shutdown(SocketShutdown.Both);
        socket.Close();
      }
    }

    private Thread recListenThread;

  }

前台调用，声明Timer定时器，每个一秒触发一次。触发事件如下：

private string flag = "";
    private void QueryTimer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
    {
      Now = DateTime.Now;

      if (!tcp.Send("MEAS:VOLTage:ALL?\n"))
      {
        queryTimer.Enabled = false;
        StartCOntent= "开始";
        COnnContent= "连接";
        tcp.IsCOnnected= false;
        MessageBox.Show("查询失败！");
        return;
      }
      flag = "V";
      Thread.Sleep(50);

      if (!tcp.Send("MEAS:CURR:ALL?\n"))
      {
        queryTimer.Enabled = false;
        StartCOntent= "开始";
        COnnContent= "连接";
        tcp.IsCOnnected= false;
        MessageBox.Show("查询失败！");
        return;
      }
      flag = "C";

      #region 测试
      //angle += 18;
      //if (angle > 360)
      //{
      //  angle = 18;
      //}

      #endregion
    }

刷新UI界面的事件如下：

private void Tcp_ReceiveEvent()
    {
      Task.Run(() =>
      {
        Application.Current.Dispatcher.Invoke(() =>
        {
          RemoteIP = tcp.TagetIPEP.ToString();
          switch (flag)
          {
            case "V":
              VoltValue = Math.Round(Convert.ToDouble(tcp.ReceiveStr.Split(',')[0]), 3);
              break;
            case "C":
              CurrentValue = Math.Round(Convert.ToDouble(tcp.ReceiveStr.Split(',')[0]), 3);
              break;
            default:
              break;
          }

          #region 测试
          //VoltValue = Math.Round(Math.Sin((angle) * pi / 180) * 16 + 16, 3);
          //CurrentValue = Math.Round(Math.Sin((angle) * pi / 180) * 2.5 + 2.5, 3);
          #endregion

          VoltValues.Add(VoltValue);
          CurrentValues.Add(CurrentValue);

          if (VoltValues.Count > 30)
          {
            VoltValues.RemoveAt(0);
            CurrentValues.RemoveAt(0);
          }
        });
      });
    }