通常，在C#中实现串口通信，我们有四种方法：
第一：通过MSCOMM控件这是最简单的，最方便的方法。可功能上很难做到控制自如，同时这个控件并不是系统本身所带，所以还得注册。可以访问 http://www.devhood.com/tutorials/tutorial_details.aspx?tutorial_id=320 一个外国人写的教程 第二：微软在.NET新推出了一个串口控件，基于.NET的P/Invoke调用方法实现，详细的可以访问微软网站 Serial Comm Use P/Invoke to Develop a .NET Base Class Library for Serial Device Communications
http://msdn.microsoft.com/msdnmag/issues/02/10/netserialcomm/ 第三：就是用第三方控件啦，可一般都要付费的，不太合实际，何况楼主不喜欢，不作考虑 第四：自己用API写串口通信，这样难度高点，但对于我们来说，可以方便实现自己想要的各种功能。
我们采用第四种方法来实现串口通信，用现成的已经封装好的类库，常见两个串口操作类是JustinIO和SerialStreamReader。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();
整合代码： using System; using System.Runtime.InteropServices;
namespace JustinIO { class CommPort {
public int 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;
//comm port win32 file handle private int hComm = -1;
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;
[StructLayout(LayoutKind.Sequential)] public struct DCB { //taken from c struct in platform sdk public int DCBlength; // sizeof(DCB) public int BaudRate; // current baud rate /* these are the c struct bit fields, bit twiddle flag to set public int fBinary; // binary mode, no EOF check public int fParity; // enable parity checking public int fOutxCtsFlow; // CTS output flow control public int fOutxDsrFlow; // DSR output flow control public int fDtrControl; // DTR flow control type public int fDsrSensitivity; // DSR sensitivity public int fTXContinueOnXoff; // XOFF continues Tx public int fOutX; // XON/XOFF out flow control public int fInX; // XON/XOFF in flow control public int fErrorChar; // enable error replacement public int fNull; // enable null stripping public int fRtsControl; // RTS flow control public int fAbortOnError; // abort on error public int fDummy2; // reserved */ public uint flags; public ushort wReserved; // not currently used public ushort XonLim; // transmit XON threshold public ushort XoffLim; // transmit XOFF threshold public byte ByteSize; // number of bits/byte, 4-8 public byte Parity; // 0-4=no,odd,even,mark,space public byte StopBits; // 0,1,2 = 1, 1.5, 2 public char XonChar; // Tx and Rx XON character public char XoffChar; // Tx and Rx XOFF character public char ErrorChar; // error replacement character public char EofChar; // end of input character public char EvtChar; // received event character public ushort wReserved1; // 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, // file name uint dwDesiredAccess, // access mode int dwShareMode, // share mode int lpSecurityAttributes, // SD int dwCreationDisposition, // how to create int dwFlagsAndAttributes, // file attributes int hTemplateFile // handle to template file ); [DllImport("kernel32.dll")] private static extern bool GetCommState( int hFile, // handle to communications device ref DCB lpDCB // device-control block ); [DllImport("kernel32.dll")] private static extern bool BuildCommDCB( string lpDef, // device-control string ref DCB lpDCB // device-control block ); [DllImport("kernel32.dll")] private static extern bool SetCommState( int hFile, // handle to communications device ref DCB lpDCB // device-control block ); [DllImport("kernel32.dll")] private static extern bool GetCommTimeouts( int hFile, // handle to comm device ref COMMTIMEOUTS lpCommTimeouts // time-out values ); [DllImport("kernel32.dll")] private static extern bool SetCommTimeouts( int hFile, // handle to comm device ref COMMTIMEOUTS lpCommTimeouts // time-out values ); [DllImport("kernel32.dll")] private static extern bool ReadFile( int hFile, // handle to file byte[] lpBuffer, // data buffer int nNumberOfBytesToRead, // number of bytes to read ref int lpNumberOfBytesRead, // number of bytes read ref OVERLAPPED lpOverlapped // overlapped buffer ); [DllImport("kernel32.dll")] private static extern bool WriteFile( int hFile, // handle to file byte[] lpBuffer, // data buffer int nNumberOfBytesToWrite, // number of bytes to write ref int lpNumberOfBytesWritten, // number of bytes written ref OVERLAPPED lpOverlapped // 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();
// OPEN THE COMM PORT.
hComm = CreateFile("COM" PortNum ,GENERIC_READ | GENERIC_WRITE,0, 0,OPEN_EXISTING,0,0);
// IF THE PORT CANNOT BE OPENED, BAIL OUT. if(hComm == INVALID_HANDLE_VALUE) { throw(new ApplicationException("Comm Port Can Not Be Opened")); }
// SET THE COMM TIMEOUTS.
GetCommTimeouts(hComm,ref ctoCommPort); ctoCommPort.ReadTotalTimeoutConstant = ReadTimeout; ctoCommPort.ReadTotalTimeoutMultiplier = 0; ctoCommPort.WriteTotalTimeoutMultiplier = 0; ctoCommPort.WriteTotalTimeoutConstant = 0; SetCommTimeouts(hComm,ref ctoCommPort);
// 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=ByteSize; dcbCommPort.StopBits=StopBits; if (!SetCommState(hComm, ref dcbCommPort)) { //uint ErrorNum=GetLastError(); throw(new ApplicationException("Comm Port Can Not Be Opened")); } //unremark to see if setting took correctly //DCB dcbCommPort2 = new DCB(); //GetCommState(hComm, ref dcbCommPort2); Opened = 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("Comm Port Not Open")); } 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("Comm Port Not Open")); } } }
} }
你可以通过这个链接引用该篇文章:http://sharkdo.bokee.com/viewdiary.233265501.html
