C#串口通訊實例

轉載地址：http://huxud.blog.sohu.com/5702440.html

 

學了C＃，由於本人搞嵌入式方面的研究，不免和串口多有打交道，故用c＃作了個串口發送應用程序。由於.net2003尚未作串口控件進去，因此這個程序化了我1個星期，包括類的處理以及不少次的調試,如今已經能夠實現串口的打開併發送數據（關閉和接收沒作好，時間問題:)）,仍是等下.net2005再弄了（聽說2005把串口控件作進去了，方便了呀！）

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Runtime.InteropServices;

namespace SerialPort_628
{
 /// <summary>
 /// Form1 的摘要說明。
 /// </summary>
 public class Form1 : System.Windows.Forms.Form
 {
  private System.Windows.Forms.TextBox textBox2;
  private System.Windows.Forms.TextBox textBox4;
  private System.Windows.Forms.ComboBox comboBox1;
  private System.Windows.Forms.PictureBox pictureBox1;
  private System.Windows.Forms.TextBox SendData;
  private System.Windows.Forms.TextBox ReceiveData;
  private System.Windows.Forms.Button button1;
  private System.Windows.Forms.Button button2;
  private System.Windows.Forms.Timer timer1;
  private System.Windows.Forms.PictureBox pictureBox2;
  private System.Windows.Forms.Button button3;
  private System.Windows.Forms.ComboBox comboBox2;
  private System.ComponentModel.IContainer components;

  public Form1()
  {
   //
   // Windows 窗體設計器支持所必需的
   //
   InitializeComponent();

   //
   // TODO: 在 InitializeComponent 調用後添加任何構造函數代碼
   //
  }

  /// <summary>
  /// 清理全部正在使用的資源。
  /// </summary>
  protected override void Dispose( bool disposing )
  {
   if( disposing )
   {
    if (components != null)
    {
     components.Dispose();
    }
   }
   base.Dispose( disposing );
  }

  #region Windows 窗體設計器生成的代碼
  /// <summary>
  /// 設計器支持所需的方法 - 不要使用代碼編輯器修改
  /// 此方法的內容。
  /// </summary>
  private void InitializeComponent()
  {
   this.components = new System.ComponentModel.Container();
   this.SendData = new System.Windows.Forms.TextBox();
   this.ReceiveData = new System.Windows.Forms.TextBox();
   this.button1 = new System.Windows.Forms.Button();
   this.textBox2 = new System.Windows.Forms.TextBox();
   this.textBox4 = new System.Windows.Forms.TextBox();
   this.comboBox1 = new System.Windows.Forms.ComboBox();
   this.button2 = new System.Windows.Forms.Button();
   this.pictureBox1 = new System.Windows.Forms.PictureBox();
   this.timer1 = new System.Windows.Forms.Timer(this.components);
   this.pictureBox2 = new System.Windows.Forms.PictureBox();
   this.button3 = new System.Windows.Forms.Button();
   this.comboBox2 = new System.Windows.Forms.ComboBox();
   this.SuspendLayout();
   //
   // SendData
   //
   this.SendData.Location = new System.Drawing.Point(24, 96);
   this.SendData.Multiline = true;
   this.SendData.Name = "SendData";
   this.SendData.Size = new System.Drawing.Size(176, 184);
   this.SendData.TabIndex = 0;
   this.SendData.Text = "";
   //
   // ReceiveData
   //
   this.ReceiveData.Location = new System.Drawing.Point(488, 96);
   this.ReceiveData.Multiline = true;
   this.ReceiveData.Name = "ReceiveData";
   this.ReceiveData.Size = new System.Drawing.Size(176, 184);
   this.ReceiveData.TabIndex = 2;
   this.ReceiveData.Text = "";
   //
   // button1
   //
   this.button1.Location = new System.Drawing.Point(296, 176);
   this.button1.Name = "button1";
   this.button1.TabIndex = 3;
   this.button1.Text = "發送";
   this.button1.Click += new System.EventHandler(this.button1_Click);
   //
   // textBox2
   //
   this.textBox2.Location = new System.Drawing.Point(24, 72);
   this.textBox2.Name = "textBox2";
   this.textBox2.ReadOnly = true;
   this.textBox2.TabIndex = 4;
   this.textBox2.Text = "發送數據區";
   //
   // textBox4
   //
   this.textBox4.Location = new System.Drawing.Point(488, 72);
   this.textBox4.Name = "textBox4";
   this.textBox4.ReadOnly = true;
   this.textBox4.TabIndex = 5;
   this.textBox4.Text = "接收數據區";
   //
   // comboBox1
   //
   this.comboBox1.Items.AddRange(new object[] {
                 "COM1 ",
                 "COM2"});
   this.comboBox1.Location = new System.Drawing.Point(24, 32);
   this.comboBox1.Name = "comboBox1";
   this.comboBox1.Size = new System.Drawing.Size(64, 20);
   this.comboBox1.TabIndex = 6;
   this.comboBox1.Text = "COM1 ";
   this.comboBox1.TextChanged += new System.EventHandler(this.comboBox1_TextChanged);
   //
   // button2
   //
   this.button2.Location = new System.Drawing.Point(128, 32);
   this.button2.Name = "button2";
   this.button2.TabIndex = 7;
   this.button2.Text = "打開";
   this.button2.Click += new System.EventHandler(this.button2_Click);
   //
   // pictureBox1
   //
   this.pictureBox1.BackColor = System.Drawing.SystemColors.Control;
   this.pictureBox1.Location = new System.Drawing.Point(104, 32);
   this.pictureBox1.Name = "pictureBox1";
   this.pictureBox1.Size = new System.Drawing.Size(8, 16);
   this.pictureBox1.TabIndex = 8;
   this.pictureBox1.TabStop = false;
   //
   // timer1
   //
   this.timer1.Interval = 1000;
   this.timer1.Tick += new System.EventHandler(this.timer1_Tick);
   //
   // pictureBox2
   //
   this.pictureBox2.BackColor = System.Drawing.SystemColors.Control;
   this.pictureBox2.Location = new System.Drawing.Point(568, 40);
   this.pictureBox2.Name = "pictureBox2";
   this.pictureBox2.Size = new System.Drawing.Size(8, 16);
   this.pictureBox2.TabIndex = 11;
   this.pictureBox2.TabStop = false;
   //
   // button3
   //
   this.button3.Location = new System.Drawing.Point(592, 40);
   this.button3.Name = "button3";
   this.button3.TabIndex = 10;
   this.button3.Text = "打開";
   this.button3.Click += new System.EventHandler(this.button3_Click);
   //
   // comboBox2
   //
   this.comboBox2.Items.AddRange(new object[] {
                 "COM1 ",
                 "COM2"});
   this.comboBox2.Location = new System.Drawing.Point(488, 40);
   this.comboBox2.Name = "comboBox2";
   this.comboBox2.Size = new System.Drawing.Size(64, 20);
   this.comboBox2.TabIndex = 9;
   this.comboBox2.Text = "COM2";
   //
   // Form1
   //
   this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
   this.ClientSize = new System.Drawing.Size(696, 346);
   this.Controls.Add(this.pictureBox2);
   this.Controls.Add(this.button3);
   this.Controls.Add(this.comboBox2);
   this.Controls.Add(this.pictureBox1);
   this.Controls.Add(this.button2);
   this.Controls.Add(this.comboBox1);
   this.Controls.Add(this.textBox4);
   this.Controls.Add(this.textBox2);
   this.Controls.Add(this.button1);
   this.Controls.Add(this.ReceiveData);
   this.Controls.Add(this.SendData);
   this.Name = "Form1";
   this.Text = "Form1";
   this.ResumeLayout(false);

  }
  #endregion

  /// <summary>
  /// 應用程序的主入口點。
  /// </summary>
  [STAThread]
  static void Main()
  {
   Application.Run(new Form1());
  }
  CommPort Sport = new CommPort();
  CommPort Rport = new CommPort();
  private void button1_Click(object sender, System.EventArgs e)
  { 
   Sport.Write(System.Text.Encoding.Default.GetBytes(SendData.Text.ToString()));
   //MessageBox.Show("數據已經發送！","",MessageBoxButtons.OK,MessageBoxIcon.Asterisk);
  }

  private void button2_Click(object sender, System.EventArgs e)
  {
   Sport.PortNum =  comboBox1.Text.ToString(); //端口號
   Sport.Parity = 0; //奇偶校驗
   Sport.BaudRate = 9600;//串口通訊波特率
   Sport.ByteSize = 8; //數據位
   Sport.StopBits = 1;//中止位
   Sport.ReadTimeout = 1000; //讀超時
   if (Sport.Opened)
　   {
　　   Sport.Close();
　　   Sport.Open(); //打開串口
　      }
   else
   {
　　   Sport.Open();//打開串口
   }
   
   pictureBox1.BackColor = System.Drawing.Color.Red;
  }

  private void comboBox1_TextChanged(object sender, System.EventArgs e)
  {
   pictureBox1.BackColor = System.Drawing.Color.WhiteSmoke;
  }

  private void timer1_Tick(object sender, System.EventArgs e)
  {
   
   if(Rport.Opened)
   {
    byte[] bs = Sport.Read(1);
    ReceiveData.Text=System.Text.Encoding.ASCII.GetString(bs);
   }
   
  }

  private void button3_Click(object sender, System.EventArgs e)
  {
  
   Rport.PortNum = comboBox2.Text.ToString(); //端口號
   Rport.BaudRate = 9600;//串口通訊波特率
   Rport.Parity = 0;//奇偶校驗
   Rport.StopBits = 1;//中止位
   Rport.ByteSize = 8;//數據位
   Rport.ReadTimeout = 1000;//讀超時
   if (Rport.Opened)
　   {
　　   Rport.Close();
　　   Rport.Open(); //打開串口
　      }
   else
   {
　　   Rport.Open();//打開串口
   }
   
   pictureBox2.BackColor = System.Drawing.Color.Red;
  }
 }

 class CommPort
 {

  public string PortNum;
  public int BaudRate;
  public byte ByteSize;
  public byte Parity; // 0-4=no,odd,even,mark,space
  public byte StopBits; // 0,1,2 = 1, 1.5, 2
  public int ReadTimeout;

  public bool Opened = false;

  //win32 api constants
  private const uint GENERIC_READ = 0x80000000;
  private const uint GENERIC_WRITE = 0x40000000;
  private const int OPEN_EXISTING = 3;
  private const int INVALID_HANDLE_VALUE = -1;

  //comm port win32 file handle
  private int hComm = INVALID_HANDLE_VALUE;

  [StructLayout(LayoutKind.Sequential)]
   public struct DCB
  {
   //taken from c struct in platform sdk
   public int DCBlength; // sizeof(DCB)
   public int BaudRate; // 指定當前波特率 current baud rate
   // these are the c struct bit fields, bit twiddle flag to set
   public int fBinary; // 指定是否容許二進制模式,在windows95中必須主TRUE binary mode, no EOF check
   public int fParity; // 指定是否容許奇偶校驗 enable parity checking
   public int fOutxCtsFlow; // 指定CTS是否用於檢測發送控制，當爲TRUE是CTS爲OFF，發送將被掛起。 CTS output flow control
   public int fOutxDsrFlow; // 指定CTS是否用於檢測發送控制 DSR output flow control
   public int fDtrControl; // DTR_CONTROL_DISABLE值將DTR置爲OFF, DTR_CONTROL_ENABLE值將DTR置爲ON, DTR_CONTROL_HANDSHAKE容許DTR"握手" DTR flow control type
   public int fDsrSensitivity; // 當該值爲TRUE時DSR爲OFF時接收的字節被忽略 DSR sensitivity
   public int fTXContinueOnXoff; // 指定當接收緩衝區已滿,而且驅動程序已經發送出XoffChar字符時發送是否中止。TRUE時，在接收緩衝區接收到緩衝區已滿的字節XoffLim且驅動程序已經發送出XoffChar字符停止接收字節以後，發送繼續進行。　FALSE時，在接收緩衝區接收到表明緩衝區已空的字節XonChar且驅動程序已經發送出恢復發送的XonChar以後，發送繼續進行。XOFF continues Tx
   public int fOutX; // TRUE時，接收到XoffChar以後便中止發送接收到XonChar以後將從新開始 XON/XOFF out flow control
   public int fInX; // TRUE時，接收緩衝區接收到表明緩衝區滿的XoffLim以後，XoffChar發送出去接收緩衝區接收到表明緩衝區空的XonLim以後，XonChar發送出去 XON/XOFF in flow control
   public int fErrorChar; // 該值爲TRUE且fParity爲TRUE時，用ErrorChar 成員指定的字符代替奇偶校驗錯誤的接收字符 enable error replacement
   public int fNull; // eTRUE時，接收時去掉空（0值）字節 enable null stripping
   public int fRtsControl; // RTS flow control
   

   public int fAbortOnError; // TRUE時,有錯誤發生時停止讀和寫操做 abort on error
   public int fDummy2; // 未使用 reserved

   public uint flags;
   public ushort wReserved; // 未使用,必須爲0 not currently used
   public ushort XonLim; // 指定在XON字符發送這前接收緩衝區中可容許的最小字節數 transmit XON threshold
   public ushort XoffLim; // 指定在XOFF字符發送這前接收緩衝區中可容許的最小字節數 transmit XOFF threshold
   public byte ByteSize; // 指定端口當前使用的數據位 number of bits/byte, 4-8
   public byte Parity; // 指定端口當前使用的奇偶校驗方法,可能爲:EVENPARITY,MARKPARITY,NOPARITY,ODDPARITY 0-4=no,odd,even,mark,space
   public byte StopBits; // 指定端口當前使用的中止位數,可能爲:ONESTOPBIT,ONE5STOPBITS,TWOSTOPBITS 0,1,2 = 1, 1.5, 2
   public char XonChar; // 指定用於發送和接收字符XON的值 Tx and Rx XON character
   public char XoffChar; // 指定用於發送和接收字符XOFF值 Tx and Rx XOFF character
   public char ErrorChar; // 本字符用來代替接收到的奇偶校驗發生錯誤時的值 error replacement character
   public char EofChar; // 當沒有使用二進制模式時,本字符可用來指示數據的結束 end of input character
   public char EvtChar; // 當接收到此字符時,會產生一個事件 received event character
   public ushort wReserved1; // 未使用 reserved; do not use
  }

  [StructLayout(LayoutKind.Sequential)]
   private struct COMMTIMEOUTS
  {
   public int ReadIntervalTimeout;
   public int ReadTotalTimeoutMultiplier;
   public int ReadTotalTimeoutConstant;
   public int WriteTotalTimeoutMultiplier;
   public int WriteTotalTimeoutConstant;
  }

  [StructLayout(LayoutKind.Sequential)]
   private struct OVERLAPPED
  {
   public int Internal;
   public int InternalHigh;
   public int Offset;
   public int OffsetHigh;
   public int hEvent;
  }

  [DllImport("kernel32.dll")]
  private static extern int CreateFile(
   string lpFileName, // 要打開的串口名稱
   uint dwDesiredAccess, // 指定串口的訪問方式，通常設置爲可讀可寫方式
   int dwShareMode, // 指定串口的共享模式，串口不能共享，因此設置爲0
   int lpSecurityAttributes, // 設置串口的安全屬性，WIN9X下不支持，應設爲NULL
   int dwCreationDisposition, // 對於串口通訊，建立方式只能爲OPEN_EXISTING
   int dwFlagsAndAttributes, // 指定串口屬性與標誌，設置爲FILE_FLAG_OVERLAPPED(重疊I/O操做)，指定串口以異步方式通訊
   int hTemplateFile // 對於串口通訊必須設置爲NULL
   );
  [DllImport("kernel32.dll")]
  private static extern bool GetCommState(
   int hFile, //通訊設備句柄
   ref DCB lpDCB // 設備控制塊DCB
   );
  [DllImport("kernel32.dll")]
  private static extern bool BuildCommDCB(
   string lpDef, // 設備控制字符串
   ref DCB lpDCB // 設備控制塊
   );
  [DllImport("kernel32.dll")]
  private static extern bool SetCommState(
   int hFile, // 通訊設備句柄
   ref DCB lpDCB // 設備控制塊
   );
  [DllImport("kernel32.dll")]
  private static extern bool GetCommTimeouts(
   int hFile, // 通訊設備句柄 handle to comm device
   ref COMMTIMEOUTS lpCommTimeouts // 超時時間 time-out values
   );
  [DllImport("kernel32.dll")]
  private static extern bool SetCommTimeouts(
   int hFile, // 通訊設備句柄 handle to comm device
   ref COMMTIMEOUTS lpCommTimeouts // 超時時間 time-out values
   );
  [DllImport("kernel32.dll")]
  private static extern bool ReadFile(
   int hFile, // 通訊設備句柄 handle to file
   byte[] lpBuffer, // 數據緩衝區 data buffer
   int nNumberOfBytesToRead, // 多少字節等待讀取 number of bytes to read
   ref int lpNumberOfBytesRead, // 讀取多少字節 number of bytes read
   ref OVERLAPPED lpOverlapped // 溢出緩衝區 overlapped buffer
   );
  [DllImport("kernel32.dll")]
  private static extern bool WriteFile(
   int hFile, // 通訊設備句柄 handle to file
   byte[] lpBuffer, // 數據緩衝區 data buffer
   int nNumberOfBytesToWrite, // 多少字節等待寫入 number of bytes to write
   ref int lpNumberOfBytesWritten, // 已經寫入多少字節 number of bytes written
   ref OVERLAPPED lpOverlapped // 溢出緩衝區 overlapped buffer
   );
  [DllImport("kernel32.dll")]
  private static extern bool CloseHandle(
   int hObject // handle to object
   );
  [DllImport("kernel32.dll")]
  private static extern uint GetLastError();

  public void Open()
  {

   DCB dcbCommPort = new DCB();
   COMMTIMEOUTS ctoCommPort = new COMMTIMEOUTS();

   // 打開串口 OPEN THE COMM PORT.
   hComm = CreateFile(PortNum ,GENERIC_READ | GENERIC_WRITE,0, 0,OPEN_EXISTING,0,0);
   // 若是串口沒有打開，就打開 IF THE PORT CANNOT BE OPENED, BAIL OUT.   
   if(hComm == INVALID_HANDLE_VALUE)
   {
    throw(new ApplicationException("串口被佔用，不能打開串口！"));
   }

   // 設置通訊超時時間 SET THE COMM TIMEOUTS.
   GetCommTimeouts(hComm,ref ctoCommPort);
   ctoCommPort.ReadIntervalTimeout = Int32.MaxValue;
   ctoCommPort.ReadTotalTimeoutConstant = 0;
   ctoCommPort.ReadTotalTimeoutMultiplier = 0;
   ctoCommPort.WriteTotalTimeoutMultiplier = 10;
   ctoCommPort.WriteTotalTimeoutConstant = 1000;
   SetCommTimeouts(hComm,ref ctoCommPort);

   // 設置串口 SET BAUD RATE, PARITY, WORD SIZE, AND STOP BITS.
   dcbCommPort.DCBlength = Marshal.SizeOf(dcbCommPort);
   GetCommState(hComm, ref dcbCommPort);
   dcbCommPort.BaudRate=BaudRate;
   dcbCommPort.Parity=Parity;
   dcbCommPort.ByteSize=ByteSize;
   dcbCommPort.StopBits=StopBits;
   SetCommState(hComm, ref dcbCommPort);
   Opened = true;
  }

  public void Close()
  {
   if (hComm!=INVALID_HANDLE_VALUE)
   {
    CloseHandle(hComm);
    hComm = INVALID_HANDLE_VALUE;
    Opened = false;
    PortNum = null;
   }
   
  }

  public byte[] Read(int NumBytes)
  {
   byte[] BufBytes;
   byte[] OutBytes;
   BufBytes = new byte[NumBytes];
   if (hComm!=INVALID_HANDLE_VALUE)
   {
    OVERLAPPED ovlCommPort = new OVERLAPPED();
    int BytesRead=0;
    ReadFile(hComm,BufBytes,NumBytes,ref BytesRead,ref ovlCommPort);
    OutBytes = new byte[BytesRead];
    Array.Copy(BufBytes,OutBytes,BytesRead);
   }
   else
   {
    throw(new ApplicationException("串口未打開！"));
   }
   return OutBytes;
  }

  public void Write(byte[] WriteBytes)
  {
   if (hComm!=INVALID_HANDLE_VALUE)
   {
    OVERLAPPED ovlCommPort = new OVERLAPPED();
    int BytesWritten = 0;
    WriteFile(hComm,WriteBytes,WriteBytes.Length,ref BytesWritten,ref ovlCommPort);
   }
   else
   {
    throw(new ApplicationException("串口未打開！"));
   }
  }
 }

 }