串口通信类JustinIO.CommPort及使用方法

 
  using System;
 
 using System.Runtime.InteropServices;
 
 using System.Text;
 
 namespace JustinIO
 {
 
     public class CommPort
     {
 
         public string PortName;
 
         public int BaudRate;
 
         public byte DataBits;
 
         public byte Parity; // 0-4=no,odd,even,mark,space 
 
         public byte StopBits; // 0,1,2 = 1, 1.5, 2 
 
         public int ReadTimeout;
 
         //comm port win32 file handle
 
         private int hComm = -1;
 
         public bool Opened = false;
 
         public bool IsOpen = 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;
 
         [StructLayout(LayoutKind.Sequential)]
 
         public struct DCB
         {
 
             //taken from c struct in platform sdk 
 
             public int DCBlength; // sizeof(DCB) 
 
             public int BaudRate; // 指定当前波特率 current baud rate
 
             // these are the c struct bit fields, bit twiddle flag to set
 
             public int fBinary; // 指定是否允许二进制模式,在windows95中必须主TRUE binary mode, no EOF check 
 
             public int fParity; // 指定是否允许奇偶校验 enable parity checking 
 
             public int fOutxCtsFlow; // 指定CTS是否用于检测发送控制，当为TRUE是CTS为OFF，发送将被挂起。 CTS output flow control 
 
             public int fOutxDsrFlow; // 指定CTS是否用于检测发送控制 DSR output flow control 
 
             public int fDtrControl; // DTR_CONTROL_DISABLE值将DTR置为OFF, DTR_CONTROL_ENABLE值将DTR置为ON, DTR_CONTROL_HANDSHAKE允许DTR"握手" DTR flow control type 
 
             public int fDsrSensitivity; // 当该值为TRUE时DSR为OFF时接收的字节被忽略 DSR sensitivity 
 
             public int fTXContinueOnXoff; // 指定当接收缓冲区已满,并且驱动程序已经发送出XoffChar字符时发送是否停止。TRUE时，在接收缓冲区接收到缓冲区已满的字节XoffLim且驱动程序已经发送出XoffChar字符中止接收字节之后，发送继续进行。　FALSE时，在接收缓冲区接收到代表缓冲区已空的字节XonChar且驱动程序已经发送出恢复发送的XonChar之后，发送继续进行。XOFF continues Tx 
 
             public int fOutX; // TRUE时，接收到XoffChar之后便停止发送接收到XonChar之后将重新开始 XON/XOFF out flow control 
 
             public int fInX; // TRUE时，接收缓冲区接收到代表缓冲区满的XoffLim之后，XoffChar发送出去接收缓冲区接收到代表缓冲区空的XonLim之后，XonChar发送出去 XON/XOFF in flow control 
 
             public int fErrorChar; // 该值为TRUE且fParity为TRUE时，用ErrorChar 成员指定的字符代替奇偶校验错误的接收字符 enable error replacement 
 
             public int fNull; // eTRUE时，接收时去掉空（0值）字节 enable null stripping 
 
             public int fRtsControl; // RTS flow control 
 
             /*RTS_CONTROL_DISABLE时,RTS置为OFF
               
             RTS_CONTROL_ENABLE时, RTS置为ON
 
             RTS_CONTROL_HANDSHAKE时,
 
             当接收缓冲区小于半满时RTS为ON
 
             当接收缓冲区超过四分之三满时RTS为OFF
 
             RTS_CONTROL_TOGGLE时,
 
             当接收缓冲区仍有剩余字节时RTS为ON ,否则缺省为OFF*/
 
             public int fAbortOnError; // TRUE时,有错误发生时中止读和写操作 abort on error 
 
             public int fDummy2; // 未使用 reserved 
 
             public uint flags;
 
             public ushort wReserved; // 未使用,必须为0 not currently used 
 
             public ushort XonLim; // 指定在XON字符发送这前接收缓冲区中可允许的最小字节数 transmit XON threshold 
 
             public ushort XoffLim; // 指定在XOFF字符发送这前接收缓冲区中可允许的最小字节数 transmit XOFF threshold 
 
             public byte ByteSize; // 指定端口当前使用的数据位 number of bits/byte, 4-8 
 
             public byte Parity; // 指定端口当前使用的奇偶校验方法,可能为:EVENPARITY,MARKPARITY,NOPARITY,ODDPARITY 0-4=no,odd,even,mark,space 
 
             public byte StopBits; // 指定端口当前使用的停止位数,可能为:ONESTOPBIT,ONE5STOPBITS,TWOSTOPBITS 0,1,2 = 1, 1.5, 2 
 
             public char XonChar; // 指定用于发送和接收字符XON的值 Tx and Rx XON character 
 
             public char XoffChar; // 指定用于发送和接收字符XOFF值 Tx and Rx XOFF character 
 
             public char ErrorChar; // 本字符用来代替接收到的奇偶校验发生错误时的值 error replacement character 
 
             public char EofChar; // 当没有使用二进制模式时,本字符可用来指示数据的结束 end of input character 
 
             public char EvtChar; // 当接收到此字符时,会产生一个事件 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, // 要打开的串口名称
 
         uint dwDesiredAccess, // 指定串口的访问方式，一般设置为可读可写方式
 
         int dwShareMode, // 指定串口的共享模式，串口不能共享，所以设置为0
 
         int lpSecurityAttributes, // 设置串口的安全属性，WIN9X下不支持，应设为NULL
 
         int dwCreationDisposition, // 对于串口通信，创建方式只能为OPEN_EXISTING
 
         int dwFlagsAndAttributes, // 指定串口属性与标志，设置为FILE_FLAG_OVERLAPPED(重叠I/O操作)，指定串口以异步方式通信
 
         int hTemplateFile // 对于串口通信必须设置为NULL
 
         );
 
         [DllImport("kernel32.dll")]
 
         private static extern bool GetCommState(
 
         int hFile, //通信设备句柄
 
         ref DCB lpDCB // 设备控制块DCB
 
         );
 
         [DllImport("kernel32.dll")]
 
         private static extern bool BuildCommDCB(
 
         string lpDef, // 设备控制字符串
 
         ref DCB lpDCB // 设备控制块
 
         );
 
         [DllImport("kernel32.dll")]
 
         private static extern bool SetCommState(
 
         int hFile, // 通信设备句柄
 
         ref DCB lpDCB // 设备控制块
 
         );
 
         [DllImport("kernel32.dll")]
 
         private static extern bool GetCommTimeouts(
 
         int hFile, // 通信设备句柄 handle to comm device
 
         ref COMMTIMEOUTS lpCommTimeouts // 超时时间 time-out values
 
         );
 
         [DllImport("kernel32.dll")]
 
         private static extern bool SetCommTimeouts(
 
         int hFile, // 通信设备句柄 handle to comm device
 
         ref COMMTIMEOUTS lpCommTimeouts // 超时时间 time-out values
 
         );
 
         [DllImport("kernel32.dll")]
 
         private static extern bool ReadFile(
 
         int hFile, // 通信设备句柄 handle to file
 
         byte[] lpBuffer, // 数据缓冲区 data buffer
 
         int nNumberOfBytesToRead, // 多少字节等待读取 number of bytes to read
 
         ref int lpNumberOfBytesRead, // 读取多少字节 number of bytes read
 
         ref OVERLAPPED lpOverlapped // 溢出缓冲区 overlapped buffer
 
         );
 
         [DllImport("kernel32.dll")]
 
         private static extern bool WriteFile(
 
         int hFile, // 通信设备句柄 handle to file
 
         byte[] lpBuffer, // 数据缓冲区 data buffer
 
         int nNumberOfBytesToWrite, // 多少字节等待写入 number of bytes to write
 
         ref int lpNumberOfBytesWritten, // 已经写入多少字节 number of bytes written
 
         ref OVERLAPPED lpOverlapped // 溢出缓冲区 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();
 
             // 打开串口 OPEN THE COMM PORT.
 
             string num = PortName.Replace("COM", "");
 
             if (int.Parse(num) >= 10)
 
                 hComm = CreateFile("//./"" + PortName, GENERIC_READ | GENERIC_WRITE, 0, 0, OPEN_EXISTING, 0, 0);
 
             else
 
                 hComm = CreateFile(PortName, GENERIC_READ | GENERIC_WRITE, 0, 0, OPEN_EXISTING, 0, 0);
 
             // 如果串口没有打开，就打开 IF THE PORT CANNOT BE OPENED, BAIL OUT.
 
             if (hComm == INVALID_HANDLE_VALUE)
             {
 
                 throw (new Exception("非法操作，不能打开串口！"));
 
             }
 
             // 设置通信超时时间 SET THE COMM TIMEOUTS.
 
             GetCommTimeouts(hComm, ref ctoCommPort);
 
             ctoCommPort.ReadTotalTimeoutConstant = ReadTimeout;
 
             ctoCommPort.ReadTotalTimeoutMultiplier = 0;
 
             ctoCommPort.WriteTotalTimeoutMultiplier = 0;
 
             ctoCommPort.WriteTotalTimeoutConstant = 0;
 
             SetCommTimeouts(hComm, ref ctoCommPort);
 
             // 设置串口 SET BAUD RATE, PARITY, WORD SIZE, AND STOP BITS.
 
             GetCommState(hComm, ref dcbCommPort);
 
             dcbCommPort.BaudRate = BaudRate;
 
             dcbCommPort.flags = 0;
 
             //dcb.fBinary=1;
 
             dcbCommPort.flags |= 1;
 
             if (Parity > 0)
             {
 
                 //dcb.fParity=1
 
                 dcbCommPort.flags |= 2;
 
             }
 
             dcbCommPort.Parity = Parity;
 
             dcbCommPort.ByteSize = DataBits;
 
             dcbCommPort.StopBits = StopBits;
 
             if (!SetCommState(hComm, ref dcbCommPort))
             {
 
                 //uint ErrorNum=GetLastError();
 
                 throw (new ApplicationException("非法操作，不能打开串口！"));
 
             }
 
             //unremark to see if setting took correctly
 
             //DCB dcbCommPort2 = new DCB();
 
             //GetCommState(hComm, ref dcbCommPort2);
 
             Opened = true;
 
             IsOpen = true;
 
         }
 
         public void Close()
         {
 
             if (hComm != INVALID_HANDLE_VALUE)
             {
 
                 CloseHandle(hComm);
 
             }
 
         }
 
         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("串口未打开！"));
 
             }
 
             return OutBytes;
 
         }
 
         public string ReadExisting()
         {
 
             return Encoding.ASCII.GetString(Read(128));
 
         }
 
         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("串口未打开！"));
 
             }
 
         }
 
         public void Write(string WriteString, Encoding CoderType)
         {
 
             Write(CoderType.GetBytes(WriteString));
 
         }
 
         public void Write(string WriteString)
         {
 
             Write(Encoding.ASCII.GetBytes(WriteString));
 
         }
 
     }
 
 }
介绍JustinIO的使用方法：

打开串口：

函数原型：public void Open()

说明：打开事先设置好的端口

示例：

using JustinIO;

static JustinIO.CommPort ss_port = new JustinIO.CommPort();
ss_port.PortNum = COM1; //端口号
ss_port.BaudRate = 19200; //串口通信波特率
ss_port.ByteSize = 8; //数据位
ss_port.Parity = 0; //奇偶校验
ss_port.StopBits = 1;//停止位
ss_port.ReadTimeout = 1000; //读超时
try
{
if (ss_port.Opened)
{
ss_port.Close();
ss_port.Open(); //打开串口
}
else
{
ss_port.Open();//打开串口
}
return true;
}
catch(Exception e)
{
MessageBox.Show("错误：" + e.Message);
return false;
}

写串口：

函数原型：public void Write(byte[] WriteBytes)

WriteBytes 就是你的写入的字节，注意，字符串要转换成字节数组才能进行通信

示例：

ss_port.Write(Encoding.ASCII.GetBytes("AT+CGMI/r")); //获取手机品牌

读串口：

函数原型：public byte[] Read(int NumBytes)

NumBytes 读入缓存数，注意读取来的是字节数组，要实际应用中要进行字符转换

示例：

string response = Encoding.ASCII.GetString(ss_port.Read(128)); //读取128个字节缓存

关闭串口：

函数原型：ss_port.Close()

示例：

ss_port.Close();