登 录
网上这方面三方类多如牛毛，真不知道用哪个好，不过不管用哪个，一定要在严格检查完善后再使用，不然给以后通信埋下隐患，只会让以后的调试会更痛苦!
ComAccess.h
//////////////////////////////////////////////////////////////////////<br /> //<br /> // ComAccess.h: interface for the CComAccess class.<br /> //<br /> //////////////////////////////////////////////////////////////////////</p> <p>#if !defined(AFX_COMACCESS_H__F15FFC6E_D059_4E57_97CD_A672C05FF9B7__INCLUDED_)<br /> #define AFX_COMACCESS_H__F15FFC6E_D059_4E57_97CD_A672C05FF9B7__INCLUDED_</p> <p>#if _MSC_VER > 1000<br /> #pragma once<br /> #endif // _MSC_VER > 1000</p> <p>class CComAccess<br /> {<br /> private:</p> <p> HANDLE m_hCom; // Device handle </p> <p> OVERLAPPED m_ov; // A structure that contains informations which are<br /> // used for asynchronous input and output operations</p> <p> TCHAR m_lpszErrorMessage[256];</p> <p>public:</p> <p> CComAccess();<br /> CComAccess(LPCSTR lpszPortNum);</p> <p> ~CComAccess();<br /> // For more definitions see <winbase.h><br /> BOOL Open(LPCSTR lpszPortNum = "com1",<br /> DWORD dwBaudRate = CBR_9600,<br /> BYTE byParity = NOPARITY,<br /> BYTE byStopBits = ONESTOPBIT,<br /> BYTE byByteSize = 8);</p> <p> VOID Close();</p> <p> DWORD WriteData(LPCVOID pdata, DWORD len);<br /> DWORD ReadData(LPVOID pdest, DWORD len, DWORD dwMaxWait = 500);</p> <p> LPSTR GetErrorMessage(VOID) { return m_lpszErrorMessage; }</p> <p>private:</p> <p> VOID ErrorToString(LPCSTR lpszMessage);</p> <p> BOOL IsNT(VOID);<br /> };</p> <p>#endif // !defined(AFX_COMACCESS_H__F15FFC6E_D059_4E57_97CD_A672C05FF9B7__INCLUDED_)
ComAccess.cpp
//////////////////////////////////////////////////////////////////////<br /> //<br /> // ComAccess.cpp: implementation of the CComAccess class.<br /> //<br /> //////////////////////////////////////////////////////////////////////</p> <p>#include "stdafx.h"<br /> #include "ComAccess.h"</p> <p>#ifdef _DEBUG<br /> #undef THIS_FILE<br /> static char THIS_FILE[]=__FILE__;<br /> #define new DEBUG_NEW<br /> #endif</p> <p>//////////////////////////////////////////////////////////////////////<br /> // Construction/Destruction<br /> //////////////////////////////////////////////////////////////////////</p> <p>CComAccess::CComAccess(VOID)<br /> {<br /> m_hCom = 0;<br /> m_lpszErrorMessage[0] = '/0';<br /> ZeroMemory(&m_ov, sizeof(m_ov));<br /> }</p> <p>CComAccess::CComAccess(LPCSTR lpszPortNum)<br /> {<br /> CComAccess::CComAccess();<br /> CComAccess::Open(lpszPortNum);<br /> }</p> <p>CComAccess::~CComAccess()<br /> {<br /> Close();<br /> }</p> <p>////////////////////////////////////////////////////////////////////////////////////////<br /> //<br /> // Function: Open(LPCSTR lpszPortNum,<br /> // DWORD dwBaudRate,<br /> // BYTE byParity,<br /> // BYTE byStopBits,<br /> // BYTE byByteSize)<br /> //<br /> // Return value: BOOL TRUE or FALSE<br /> //</p> <p>BOOL CComAccess::Open(LPCSTR lpszPortNum,<br /> DWORD dwBaudRate,<br /> BYTE byParity,<br /> BYTE byStopBits,<br /> BYTE byByteSize)<br /> {<br /> DCB dcb; // structure that defines the control setting for a serial communications device<br /> BOOL bSuccess;</p> <p> m_hCom = CreateFile(lpszPortNum, // pointer to name of the file<br /> GENERIC_READ|GENERIC_WRITE, // access mode<br /> 0, // comm devices must be opened w/exclusive-access<br /> NULL, // no security attributs<br /> OPEN_EXISTING, // comm devices must use OPEN_EXISTING<br /> FILE_FLAG_OVERLAPPED, // overlapped I/O<br /> NULL); // hTemplate must be NULL for comm devices </p> <p> if ( m_hCom == INVALID_HANDLE_VALUE )<br /> {<br /> // handle the error<br /> CComAccess::ErrorToString("Open(): CreateFile() failed, invalid handle value");</p> <p> return FALSE;<br /> }</p> <p> //<br /> // Omit the call to SetupComm to use the default queue sizes.<br /> // Get the current configuration.<br /> //</p> <p> bSuccess = GetCommState(m_hCom, &dcb);</p> <p> if ( ! bSuccess )<br /> {<br /> // Handle the error.<br /> CComAccess::ErrorToString("Open(): GetCommState() failed");<br /> CComAccess::Close();</p> <p> return FALSE;<br /> }</p> <p> //<br /> // Fill in the DCB: baud=9600, 8 data bits, no parity, 1 stop bit are default parameters<br /> //</p> <p> dcb.BaudRate = dwBaudRate;<br /> dcb.ByteSize = byByteSize;<br /> dcb.Parity = byParity;<br /> dcb.StopBits = byStopBits;</p> <p> bSuccess = SetCommState(m_hCom, &dcb);</p> <p> if ( ! bSuccess )<br /> {<br /> // Handle the error.<br /> CComAccess::ErrorToString("Open(): SetCommState() failed");<br /> CComAccess::Close();</p> <p> return FALSE;<br /> }</p> <p> return TRUE;<br /> }</p> <p>////////////////////////////////////////////////////////////////////////////////////////<br /> //<br /> // Function: Close(VOID)<br /> //<br /> // Return value: VOID<br /> //</p> <p>VOID CComAccess::Close()<br /> {<br /> if ( m_hCom > 0 )<br /> {<br /> CloseHandle(m_hCom);<br /> }</p> <p> m_hCom = 0;<br /> }</p> <p>////////////////////////////////////////////////////////////////////////////////////////<br /> //<br /> // Function: WriteData(LPCVOID pdata,<br /> // DWORD len)<br /> //<br /> // Return value: DWORD -1 failed, above, num written bytes<br /> //</p> <p>DWORD CComAccess::WriteData(LPCVOID pdata,<br /> DWORD len)<br /> {<br /> BOOL bSuccess;<br /> DWORD written = 0;</p> <p> if ( len < 1 )<br /> return(0);</p> <p> // create event for overlapped I/O<br /> m_ov.hEvent = CreateEvent(NULL, // pointer to security attributes<br /> FALSE, // flag for manual-reset event<br /> FALSE, // flag for initial state<br /> ""); // pointer to event-object name </p> <p> if ( m_ov.hEvent == INVALID_HANDLE_VALUE )<br /> {<br /> // Handle the error.<br /> CComAccess::ErrorToString("WriteData(): CreateEvent() failed");</p> <p> return(-1);<br /> }</p> <p> bSuccess = WriteFile(m_hCom, // handle to file to write to<br /> pdata, // pointer to data to write to file<br /> len, // number of bytes to write<br /> &written, // pointer to number of bytes written<br /> &m_ov); // pointer to structure needed for overlapped I/O</p> <p> if ( CComAccess::IsNT() )<br /> {<br /> bSuccess = GetOverlappedResult(m_hCom, &m_ov, &written, TRUE);</p> <p> if ( ! bSuccess )<br /> {<br /> // Handle the error.<br /> CloseHandle(m_ov.hEvent);<br /> CComAccess::ErrorToString("WriteData(): GetOverlappedResult() failed");</p> <p> return(-1);<br /> }<br /> }<br /> else<br /> if ( len != written )<br /> {<br /> // Handle the error.<br /> CloseHandle(m_ov.hEvent);<br /> CComAccess::ErrorToString("WriteData(): WriteFile() failed");</p> <p> return(-1);<br /> }</p> <p> CloseHandle(m_ov.hEvent);</p> <p> return written;<br /> }</p> <p>////////////////////////////////////////////////////////////////////////////////////////<br /> //<br /> // Function: ReadData(LPVOID pdest,<br /> // DWORD len,<br /> // DWORD dwMaxWait)<br /> //<br /> // Return value: DWORD -1 failed, above, num read bytes<br /> //</p> <p>DWORD CComAccess::ReadData(LPVOID pdest,<br /> DWORD len,<br /> DWORD dwMaxWait)<br /> {<br /> BOOL bSuccess;<br /> DWORD result = 0,<br /> read = 0, // num read bytes<br /> mask = 0; // a 32-bit variable that receives a mask<br /> // indicating the type of event that occurred</p> <p> if ( len < 1 ) return(0);</p> <p> // create event for overlapped I/O</p> <p> m_ov.hEvent = CreateEvent(NULL, // pointer to security attributes<br /> FALSE, // flag for manual-reset event<br /> FALSE, // flag for initial state<br /> ""); // pointer to event-object name </p> <p> if ( m_ov.hEvent == INVALID_HANDLE_VALUE )<br /> {<br /> // Handle the error.<br /> CComAccess::ErrorToString("ReadData(): CreateEvent() failed");</p> <p> return(-1);<br /> }</p> <p> // Specify here the event to be enabled</p> <p> bSuccess = SetCommMask(m_hCom, EV_RXCHAR);</p> <p> if ( ! bSuccess )<br /> {<br /> // Handle the error.<br /> CloseHandle(m_ov.hEvent);<br /> CComAccess::ErrorToString("ReadData(): SetCommMask() failed");</p> <p> return(-1);<br /> }</p> <p> // WaitForSingleObject</p> <p> bSuccess = WaitCommEvent(m_hCom, &mask, &m_ov);</p> <p> if ( ! bSuccess )<br /> {<br /> int err = GetLastError();</p> <p> if ( err == ERROR_IO_PENDING)<br /> {<br /> result = WaitForSingleObject(m_ov.hEvent, dwMaxWait); //wait dwMaxWait<br /> // milli seconds before returning<br /> if ( result == WAIT_FAILED )<br /> {<br /> // Handle the error.<br /> CloseHandle(m_ov.hEvent);<br /> CComAccess::ErrorToString("ReadData(): WaitForSingleObject() failed");</p> <p> return(-1);<br /> }<br /> }<br /> }</p> <p> // The specified event occured?</p> <p> if ( mask & EV_RXCHAR)<br /> {<br /> bSuccess = ReadFile(m_hCom, // handle of file to read<br /> pdest, // address of buffer that receives data<br /> len, // number of bytes to read<br /> &read, // address of number of bytes read<br /> &m_ov); // address of structure for data </p> <p> if ( CComAccess::IsNT() )<br /> {<br /> bSuccess = GetOverlappedResult(m_hCom, &m_ov, &read, TRUE);</p> <p> if ( ! bSuccess )<br /> {<br /> // Handle the error.<br /> CloseHandle(m_ov.hEvent);<br /> CComAccess::ErrorToString("WriteData(): GetOverlappedResult() failed");</p> <p> return(-1);<br /> }<br /> }<br /> else<br /> if ( ! bSuccess )<br /> {<br /> // Handle the error.<br /> CloseHandle(m_ov.hEvent);<br /> CComAccess::ErrorToString("ReadData(): ReadFile() failed");</p> <p> return(-1);<br /> }<br /> }<br /> else<br /> {<br /> // Handle the error.<br /> CloseHandle(m_ov.hEvent);<br /> wsprintf(m_lpszErrorMessage, "Error ReadData(): No EV_RXCHAR occured/n");</p> <p> return(-1);<br /> }</p> <p> CloseHandle(m_ov.hEvent);</p> <p> return read;<br /> }</p> <p>////////////////////////////////////////////////////////////////////////////////////////<br /> //<br /> // Function: ErrorToString(LPCSTR lpszMessage)<br /> //<br /> // Return value: VOID<br /> //</p> <p>VOID CComAccess::ErrorToString(LPCSTR lpszMessage)<br /> {<br /> LPVOID lpMessageBuffer;<br /> DWORD error = GetLastError();</p> <p> FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |<br /> FORMAT_MESSAGE_FROM_SYSTEM, // source and processing options<br /> NULL, // pointer to message source<br /> error, // requested message identifie<br /> MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // the user default language.<br /> (LPTSTR) &lpMessageBuffer, // pointer to message buffer<br /> 0, // maximum size of message buffer<br /> NULL); // address of array of message inserts </p> <p> // and copy it in our error string<br /> wsprintf(m_lpszErrorMessage,"%s: (%d) %s/n", lpszMessage, error, lpMessageBuffer);</p> <p> LocalFree(lpMessageBuffer);<br /> }</p> <p>////////////////////////////////////////////////////////////////////////////////////////<br /> //<br /> // Function: IsNT(VOID)<br /> //<br /> // Return value: BOOL True or False<br /> //</p> <p>BOOL CComAccess::IsNT(VOID)<br /> {<br /> OSVERSIONINFO osvi;</p> <p> osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);</p> <p> GetVersionEx(&osvi);</p> <p> if (osvi.dwPlatformId == VER_PLATFORM_WIN32_NT)<br /> {<br /> return TRUE;<br /> }<br /> else<br /> {<br /> return FALSE;<br /> }<br /> }
抱歉!评论已关闭.