what’s a virtual destructor and when is it needed?

本文通过两个示例对比了C++中普通析构函数与虚拟析构函数的区别,阐述了为何及何时需要使用虚拟析构函数。通过具体代码演示了虚拟析构函数如何确保派生类的析构函数被正确调用。

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In C++, what’s a virtual destructor and when is it needed?

The need for virtual destructors in C++ is best illustrated by some examples. Let’s start by going through an example that does not use virtual destructors, and then we will go through an example that does use virtual destructors. Once you see the difference, you will understand why virtual destructors are needed. Take a look at the code below to start out:As you may know, in C++ a destructor is generally used to deallocate memory and do some other cleanup for a class object and it’s class members whenever an object is destroyed. Destructors are distinguished by the tilde, the ‘~’ that appears in front of the destructor name. In order to define avirtual destructor, all you have to do is simply add the keyword “virtual” before the tilde symbol.


Example without a Virtual Destructor:

#include iostream.h
class Base
{
   	public:
      	Base(){ cout<<"Constructing Base";}
      	
     // this is a destructor:
	
	~Base(){ cout<<"Destroying Base";}
};

class Derive: public Base
{
        public:
       	Derive(){ cout<<"Constructing Derive";}
       	
       	~Derive(){ cout<<"Destroying Derive";}
 };

void main()
{
    	Base *basePtr = new Derive();
        
        delete basePtr;
}

The output after running the code above would be:

Constructing Base  
Constructing Derive 
Destroying Base

Based on the output above, we can see that the constructors get called in the appropriate order when we create the Derive class object pointer in the main function.

But there is a major problem with the code above: the destructor for the "Derive" class does not get called at all when we delete ‘basePtr’.

So, how can we fix this problem?

Well, what we can do is make the base class destructor virtual, and that will ensure that the destructor for any class that derives from Base (in our case, its the "Derive" class) will be called.

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Example with a Virtual Destructor:

So, the only thing we will need to change is the destructor in the Base class and here’s what it will look like – note that we highlighted the part of the code where the virtual keyword has been added in red:

class Base
{
   	public:
      	Base(){ cout<<"Constructing Base";}

	// this is a virtual destructor:
	virtual ~Base(){ cout<<"Destroying Base";}
};

Now, with that change, the output after running the code above will be:

Constructing Base  
Constructing Derive 
Destroying Derive
Destroying Base

Note that the derived class destructor will be called before the base class.

So, now you’ve seen why we need virtual destructors and also how they work.

One important design paradigm of class design is that if a class has one or more virtual functions, then that class should also have a virtual destructor.

我做了一个宠物智能投喂系统,现在我有一个stm32f103c6单片机外接8MHz的晶振,其PA1连作为RXD,PA2作为TXD,PB0、PB1连接了发光二极管的负极,发光二极管的正极接的电源,发光二极管用来模拟电机转动状态,在收到喂食的指令后PB0先亮两秒,PB1先不亮,然后在PB1亮两秒PB0熄灭,最后一起闪烁两秒表示喂食已完成,我创建了一个mfc程序(PCMFCDLG),添加了5个Combo Box控件分别用来选择端口号(控件类,m_cbPort)、波特率(控件类,m_cbBaud)、校验位(控件类,m_cbParity)、数据位(控件类,m_cbDate)以及停止位(控件类,m_cbStop),4个按钮控件分别用来打开串口连接stm32单片机、关闭串口、立即投喂、定时投喂,3个Edit control控件(value类,m_strTime1/2/3)用来定时3个时间点实现定时投喂,最后还有一个List Box(控件类,m_listStatus)用来显示执行状态,在PC机与单片机没有建立连接的时候除了连接按钮,其他按钮都不能点击,在定时按钮没有按下的时候edit control控件不能输入,在单片机执行完相应操作后,会返还给PC机信息,然后显示在list box里面如mfc界面点击立即投喂,单片机执行完操作后返回给pc端mfc界面一个标志,告诉pc端操作已完成,然后在mfc界面的list里面显示对应操作已完成。 /* Module : SerialPort.h Purpose: Interface for an C++ wrapper class for serial ports Copyright (c) 1999 - 2015 by PJ Naughter. All rights reserved. Copyright / Usage Details: You are allowed to include the source code in any product (commercial, shareware, freeware or otherwise) when your product is released in binary form. You are allowed to modify the source code in any way you want except you cannot modify the copyright details at the top of each module. If you want to distribute source code with your application, then you are only allowed to distribute versions released by the author. This is to maintain a single distribution point for the source code. */ // Macros / Structs etc #pragma once #ifndef __SERIALPORT_H__ #define __SERIALPORT_H__ #ifndef CSERIALPORT_EXT_CLASS #define CSERIALPORT_EXT_CLASS #endif //#ifndef CSERIALPORT_EXT_CLASS #ifndef _Out_writes_bytes_ #define _Out_writes_bytes_(X) #endif //#ifndef _Out_writes_bytes_ #ifndef __out_data_source #define __out_data_source(X) #endif //#ifndef __out_data_source #ifndef _Out_writes_bytes_to_opt_ #define _Out_writes_bytes_to_opt_(X,Y) #endif //#ifndef _Out_writes_bytes_to_opt_ #ifndef _Out_writes_bytes_opt_ #define _Out_writes_bytes_opt_(X) #endif //#ifndef _Out_writes_bytes_opt_ #ifndef _In_reads_bytes_opt_ #define _In_reads_bytes_opt_(X) #endif //#ifndef _In_reads_bytes_opt_ #ifndef _In_ #define _In_ #endif //#ifndef _In_ #ifndef _In_z_ #define _In_z_ #endif //#ifndef _In_z_ #ifndef _Inout_opt_ #define _Inout_opt_ #endif //#ifndef _Inout_opt_ #ifndef _Out_opt_ #define _Out_opt_ #endif //#ifndef _Out_opt_ #ifndef _Out_ #define _Out_ #endif //#ifndef _Out_ #ifndef _Inout_ #define _Inout_ #endif //#ifndef _Inout_ #ifndef _In_opt_ #define _In_opt_ #endif //#ifndef _In_opt_ // Includes /// #include <sal.h> #ifndef CSERIALPORT_MFC_EXTENSTIONS #include <exception> #include <string> #endif //#ifndef CSERIALPORT_MFC_EXTENSTIONS /// Classes /// #ifdef CSERIALPORT_MFC_EXTENSIONS class CSERIALPORT_EXT_CLASS CSerialException : public CException #else class CSERIALPORT_EXT_CLASS CSerialException : public std::exception #endif //#ifdef CSERIALPORT_MFC_EXTENSIONS { public: //Constructors / Destructors CSerialException(DWORD dwError); //Methods #ifdef CSERIALPORT_MFC_EXTENSIONS #ifdef _DEBUG virtual void Dump(CDumpContext& dc) const; #endif //#ifdef _DEBUG #endif //#ifdef CSERIALPORT_MFC_EXTENSIONS #if _MSC_VER >= 1700 virtual BOOL GetErrorMessage(_Out_z_cap_(nMaxError) LPTSTR lpszError, _In_ UINT nMaxError, _Out_opt_ PUINT pnHelpContext = NULL); #else virtual BOOL GetErrorMessage(__out_ecount_z(nMaxError) LPTSTR lpszError, __in UINT nMaxError, __out_opt PUINT pnHelpContext = NULL); #endif #ifdef CSERIALPORT_MFC_EXTENSIONS CString GetErrorMessage(); #endif //#ifdef CSERIALPORT_MFC_EXTENSIONS //Data members DWORD m_dwError; }; class CSERIALPORT_EXT_CLASS CSerialPort { public: //Enums enum FlowControl { NoFlowControl, CtsRtsFlowControl, CtsDtrFlowControl, DsrRtsFlowControl, DsrDtrFlowControl, XonXoffFlowControl }; enum Parity { NoParity = 0, OddParity = 1, EvenParity = 2, MarkParity = 3, SpaceParity = 4 }; enum StopBits { OneStopBit, OnePointFiveStopBits, TwoStopBits }; //Constructors / Destructors CSerialPort(); virtual ~CSerialPort(); //General Methods void Open(_In_ int nPort, _In_ DWORD dwBaud = 9600, _In_ Parity parity = NoParity, _In_ BYTE DataBits = 8, _In_ StopBits stopBits = OneStopBit, _In_ FlowControl fc = NoFlowControl, _In_ BOOL bOverlapped = FALSE); void Open(_In_z_ LPCTSTR pszPort, _In_ DWORD dwBaud = 9600, _In_ Parity parity = NoParity, _In_ BYTE DataBits = 8, _In_ StopBits stopBits = OneStopBit, _In_ FlowControl fc = NoFlowControl, _In_ BOOL bOverlapped = FALSE); void Close(); void Attach(_In_ HANDLE hComm); HANDLE Detach(); operator HANDLE() const { return m_hComm; }; BOOL IsOpen() const { return m_hComm != INVALID_HANDLE_VALUE; }; #ifdef CSERIALPORT_MFC_EXTENSIONS #ifdef _DEBUG void Dump(_In_ CDumpContext& dc) const; #endif //#ifdef _DEBUG #endif //#ifdef CSERIALPORT_MFC_EXTENSIONS //Reading / Writing Methods void Read(_Out_writes_bytes_(dwNumberOfBytesToRead) __out_data_source(FILE) void* lpBuffer, _In_ DWORD dwNumberOfBytesToRead); void Read(_Out_writes_bytes_to_opt_(dwNumberOfBytesToRead, *lpNumberOfBytesRead) __out_data_source(FILE) void* lpBuffer, _In_ DWORD dwNumberOfBytesToRead, _In_ OVERLAPPED& overlapped, _Inout_opt_ DWORD* lpNumberOfBytesRead = NULL); void ReadEx(_Out_writes_bytes_opt_(dwNumberOfBytesToRead) __out_data_source(FILE) LPVOID lpBuffer, _In_ DWORD dwNumberOfBytesToRead, _Inout_ LPOVERLAPPED lpOverlapped, _In_ LPOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine); DWORD Write(_In_reads_bytes_opt_(dwNumberOfBytesToWrite) const void* lpBuffer, _In_ DWORD dwNumberOfBytesToWrite); void Write(_In_reads_bytes_opt_(dwNumberOfBytesToWrite) const void* lpBuffer, _In_ DWORD dwNumberOfBytesToWrite, _In_ OVERLAPPED& overlapped, _Out_opt_ DWORD* lpNumberOfBytesWritten = NULL); void WriteEx(_In_reads_bytes_opt_(dwNumberOfBytesToWrite) LPCVOID lpBuffer, _In_ DWORD dwNumberOfBytesToWrite, _Inout_ LPOVERLAPPED lpOverlapped, _In_ LPOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine); void TransmitChar(_In_ char cChar); DWORD GetOverlappedResult(_In_ OVERLAPPED& overlapped, _Out_ DWORD& dwBytesTransferred, _In_ BOOL bWait); void CancelIo(); DWORD BytesWaiting(); DWORD BytesPending(); //Configuration Methods void GetConfig(_In_ COMMCONFIG& config); static void GetDefaultConfig(_In_ int nPort, _Out_ COMMCONFIG& config); static void GetDefaultConfig(_In_z_ LPCTSTR pszPort, _Out_ COMMCONFIG& config); void SetConfig(_In_ COMMCONFIG& Config); static void SetDefaultConfig(_In_ int nPort, _In_ COMMCONFIG& config); static void SetDefaultConfig(_In_z_ LPCTSTR pszPort, _In_ COMMCONFIG& config); //Misc RS232 Methods void ClearBreak(); void SetBreak(); void ClearError(_Out_ DWORD& dwErrors); void GetStatus(_Out_ COMSTAT& stat); void GetState(_Out_ DCB& dcb); void SetState(_In_ DCB& dcb); void Escape(_In_ DWORD dwFunc); void ClearDTR(); void ClearRTS(); void SetDTR(); void SetRTS(); void SetXOFF(); void SetXON(); void GetProperties(_Inout_ COMMPROP& properties); void GetModemStatus(_Out_ DWORD& dwModemStatus); //Timeouts void SetTimeouts(_In_ COMMTIMEOUTS& timeouts); void GetTimeouts(_Out_ COMMTIMEOUTS& timeouts); void Set0Timeout(); void Set0WriteTimeout(); void Set0ReadTimeout(); //Event Methods void SetMask(_In_ DWORD dwMask); void GetMask(_Out_ DWORD& dwMask); void WaitEvent(_Inout_ DWORD& dwMask); BOOL WaitEvent(_Inout_ DWORD& dwMask, _Inout_ OVERLAPPED& overlapped); //Queue Methods void Flush(); void Purge(_In_ DWORD dwFlags); void TerminateOutstandingWrites(); void TerminateOutstandingReads(); void ClearWriteBuffer(); void ClearReadBuffer(); void Setup(_In_ DWORD dwInQueue, _In_ DWORD dwOutQueue); //Static methods static void ThrowSerialException(_In_ DWORD dwError = 0); protected: //Member variables HANDLE m_hComm; //Handle to the comms port }; #endif //#ifndef __SERIALPORT_H__ /* Module : SerialPort.cpp Purpose: Implementation for an C++ wrapper class for serial ports Created: PJN / 31-05-1999 History: PJN / 03-06-1999 1. Fixed problem with code using CancelIo which does not exist on 95. 2. Fixed leaks which can occur in sample app when an exception is thrown PJN / 16-06-1999 1. Fixed a bug whereby CString::ReleaseBuffer was not being called in CSerialException::GetErrorMessage PJN / 29-09-1999 1. Fixed a simple copy and paste bug in CSerialPort::SetDTR PJN / 08-05-2000 1. Fixed an unreferrenced variable in CSerialPort::GetOverlappedResult in VC 6 PJN / 10-12-2000 1. Made class destructor virtual PJN / 15-01-2001 1. Attach method now also allows you to specify whether the serial port is being attached to in overlapped mode 2. Removed some ASSERTs which were unnecessary in some of the functions 3. Updated the Read method which uses OVERLAPPED IO to also return the bytes read. This allows calls to WriteFile with a zeroed overlapped structure (This is required when dealing with TAPI and serial communications) 4. Now includes copyright message in the source code and documentation. PJN / 24-03-2001 1. Added a BytesWaiting method PJN / 04-04-2001 1. Provided an overriden version of BytesWaiting which specifies a timeout PJN / 23-04-2001 1. Fixed a memory leak in DataWaiting method PJN / 01-05-2002 1. Fixed a problem in Open method which was failing to initialize the DCB structure incorrectly, when calling GetState. Thanks to Ben Newson for this fix. PJN / 29-05-2002 1. Fixed an problem where the GetProcAddress for CancelIO was using the wrong calling convention PJN / 07-08-2002 1. Changed the declaration of CSerialPort::WaitEvent to be consistent with the rest of the methods in CSerialPort which can operate in "OVERLAPPED" mode. A note about the usage of this: If the method succeeds then the overlapped operation has completed synchronously and there is no need to do a WaitForSingle/MultipleObjects. If any other unexpected error occurs then a CSerialException will be thrown. See the implementation of the CSerialPort::DataWaiting which has been rewritten to use this new design pattern. Thanks to Serhiy Pavlov for spotting this inconsistency. PJN / 20-09-2002 1. Addition of an additional ASSERT in the internal _OnCompletion function. 2. Addition of an optional out parameter to the Write method which operates in overlapped mode. Thanks to Kevin Pinkerton for this addition. PJN / 10-04-2006 1. Updated copyright details. 2. Addition of a CSERIALPORT_EXT_CLASS and CSERIALPORT_EXT_API macros which makes the class easier to use in an extension dll. 3. Removed derivation of CSerialPort from CObject as it was not really needed. 4. Fixed a number of level 4 warnings in the sample app. 5. Reworked the overlapped IO methods to expose the LPOVERLAPPED structure to client code. 6. Updated the documentation to use the same style as the web site. 7. Did a spell check of the HTML documentation. 8. Updated the documentation on possible blocking in Read/Ex function. Thanks to D Kerrison for reporting this issue. 9. Fixed a minor issue in the sample app when the code is compiled using /Wp64 PJN / 02-06-2006 1. Removed the bOverlapped as a member variable from the class. There was no real need for this setting, since the SDK functions will perform their own checking of how overlapped operations should 2. Fixed a bug in GetOverlappedResult where the code incorrectly checking against the error ERROR_IO_PENDING instead of ERROR_IO_INCOMPLETE. Thanks to Sasho Darmonski for reporting this bug. 3. Reviewed all TRACE statements for correctness. PJN / 05-06-2006 1. Fixed an issue with the creation of the internal event object. It was incorrectly being created as an auto-reset event object instead of a manual reset event object. Thanks to Sasho Darmonski for reporting this issue. PJN / 24-06-2006 1. Fixed some typos in the history list. Thanks to Simon Wong for reporting this. 2. Made the class which handles the construction of function pointers at runtime a member variable of CSerialPort 3. Made AfxThrowSerialPortException part of the CSerialPort class. Thanks to Simon Wong for reporting this. 4. Removed the unnecessary CSerialException destructor. Thanks to Simon Wong for reporting this. 5. Fixed a minor error in the TRACE text in CSerialPort::SetDefaultConfig. Again thanks to Simon Wong for reporting this. 6. Code now uses new C++ style casts rather than old style C casts where necessary. Again thanks to Simon Wong for reporting this. 7. CSerialException::GetErrorMessage now uses the strsafe functions. This does mean that the code now requires the Platform SDK if compiled using VC 6. PJN / 25-06-2006 1. Combined the functionality of the CSerialPortData class into the main CSerialPort class. 2. Renamed AfxThrowSerialPortException to ThrowSerialPortException and made the method public. PJN / 05-11-2006 1. Minor update to stdafx.h of sample app to avoid compiler warnings in VC 2005. 2. Reverted the use of the strsafe.h header file. Instead now the code uses the VC 2005 Safe CRT and if this is not available, then we fail back to the standard CRT. PJN / 25-01-2007 1. Minor update to remove strsafe.h from stdafx.h of the sample app. 2. Updated copyright details. PJN / 24-12-2007 1. CSerialException::GetErrorMessage now uses the FORMAT_MESSAGE_IGNORE_INSERTS flag. For more information please see Raymond Chen's blog at http://blogs.msdn.com/oldnewthing/archive/2007/11/28/6564257.aspx. Thanks to Alexey Kuznetsov for reporting this issue. 2. Simplified the code in CSerialException::GetErrorMessage somewhat. 3. Optimized the CSerialException constructor code. 4. Code now uses newer C++ style casts instead of C style casts. 5. Reviewed and updated all the TRACE logging in the module 6. Replaced all calls to ZeroMemory with memset PJN / 30-12-2007 1. Updated the sample app to clean compile on VC 2008 2. CSerialException::GetErrorMessage now uses Checked::tcsncpy_s if compiled using VC 2005 or later. PJN / 18-05-2008 1. Updated copyright details. 2. Changed the actual values for Parity enum so that they are consistent with the Parity define values in the Windows SDK header file WinBase.h. This avoids the potential issue where you use the CSerialPort enum parity values in a call to the raw Win32 API calls. Thanks to Robert Krueger for reporting this issue. PJN / 21-06-2008 1. Code now compiles cleanly using Code Analysis (/analyze) 2. Updated code to compile correctly using _ATL_CSTRING_EXPLICIT_CONSTRUCTORS define 3. The code now only supports VC 2005 or later. 4. CSerialPort::Read, Write, GetOverlappedResult & WaitEvent now throw an exception irrespective of whether the last error is ERROR_IO_PENDING or not 5. Replaced all calls to ZeroMemory with memset PJN / 04-07-2008 1. Provided a version of the Open method which takes a string instead of a numeric port number value. This allows the code to support some virtual serial port packages which do not use device names of the form "COM%d". Thanks to David Balazic for suggesting this addition. PJN / 25-01-2012 1. Updated copyright details. 2. Updated sample app and class to compile cleanly on VC 2010 and later. PJN / 28-02-2015 1. Updated sample project settings to more modern default values. 2. Updated copyright details. 3. Reworked the CSerialPort and CSerialPortException classes to optionally compile without MFC. By default the classes now use STL classes and idioms but if you define CSERIALPORT_MFC_EXTENSTIONS the classes will revert back to the MFC behaviour. 4. Remove logic to use GetProcAddress to access CancelIO functionality. 5. Updated the code to clean compile on VC 2013 6. Added SAL annotations to all the code 7. Addition of a GetDefaultConfig method which takes a string 8. Addition of a SetDefaultConfig method which takes a string PJN / 26-04-2015 1. Removed unnecessary inclusion of WinError.h 2. Removed the CSerialPort::DataWaiting method as it depends on the port being open in overlapped mode. Instead client code can simply call CSerialPort::WaitEvent directly themselves. Removing this method also means that the CSerialPort::m_hEvent handle has not also been removed. 3. The CSerialPort::WriteEx method has been reworked to expose all the parameters of the underlying WriteFileEx API. This rework also fixes a memory leak in WriteEx which can sometimes occur. This reworks also means that the CSerialPort::_OnCompletion and CSerialPort::_OnCompletion methods have been removed. Thanks to Yufeng Huang for reporting this issue. 4. The CSerialPort::ReadEx method has been reworked to expose all the parameters of the underlying ReadFileEx API. This rework also fixes a memory leak in ReadEx which can sometimes occur. This reworks also means that the CSerialPort::_OnCompletion and CSerialPort::_OnCompletion methods have been removed. Thanks to Yufeng Huang for reporting this issue. Copyright (c) 1996 - 2015 by PJ Naughter (Web: www.naughter.com, Email: pjna@naughter.com) All rights reserved. Copyright / Usage Details: You are allowed to include the source code in any product (commercial, shareware, freeware or otherwise) when your product is released in binary form. You are allowed to modify the source code in any way you want except you cannot modify the copyright details at the top of each module. If you want to distribute source code with your application, then you are only allowed to distribute versions released by the author. This is to maintain a single distribution point for the source code. */ // Includes #include "pch.h" #include "SerialPort.h" #ifndef __ATLBASE_H__ #pragma message("To avoid this message, please put atlbase.h in your pre compiled header (normally stdafx.h)") #include <atlbase.h> #endif //#ifndef __ATLBASE_H__ // Defines / #ifdef CSERIALPORT_MFC_EXTENSIONS #ifdef _DEBUG #define new DEBUG_NEW #endif //#ifdef _DEBUG #endif //#ifdef CSERIALPORT_MFC_EXTENSIONS //Implementation /// #if _MSC_VER >= 1700 BOOL CSerialException::GetErrorMessage(_Out_z_cap_(nMaxError) LPTSTR lpszError, _In_ UINT nMaxError, _Out_opt_ PUINT pnHelpContext) #else BOOL CSerialException::GetErrorMessage(__out_ecount_z(nMaxError) LPTSTR lpszError, __in UINT nMaxError, __out_opt PUINT pnHelpContext) #endif { //Validate our parameters ATLASSERT(lpszError != NULL); if (pnHelpContext != NULL) *pnHelpContext = 0; //What will be the return value from this function (assume the worst) BOOL bSuccess = FALSE; LPTSTR lpBuffer; DWORD dwReturn = FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, m_dwError, MAKELANGID(LANG_NEUTRAL, SUBLANG_SYS_DEFAULT), reinterpret_cast<LPTSTR>(&lpBuffer), 0, NULL); if (dwReturn == 0) *lpszError = _T('\0'); else { bSuccess = TRUE; Checked::tcsncpy_s(lpszError, nMaxError, lpBuffer, _TRUNCATE); LocalFree(lpBuffer); } return bSuccess; } #ifdef CSERIALPORT_MFC_EXTENSIONS CString CSerialException::GetErrorMessage() { CString rVal; LPTSTR pstrError = rVal.GetBuffer(4096); GetErrorMessage(pstrError, 4096, NULL); rVal.ReleaseBuffer(); return rVal; } #endif //#ifdef CSERIALPORT_MFC_EXTENSIONS CSerialException::CSerialException(DWORD dwError) : m_dwError(dwError) { } #ifdef CSERIALPORT_MFC_EXTENSIONS #ifdef _DEBUG void CSerialException::Dump(_In_ CDumpContext& dc) const { CObject::Dump(dc); dc << _T("m_dwError = ") << m_dwError << _T("\n"); } #endif //#ifdef _DEBUG #endif //#ifdef CSERIALPORT_MFC_EXTENSIONS CSerialPort::CSerialPort() : m_hComm(INVALID_HANDLE_VALUE) { } CSerialPort::~CSerialPort() { Close(); } void CSerialPort::ThrowSerialException(_In_ DWORD dwError) { if (dwError == 0) dwError = ::GetLastError(); ATLTRACE(_T("Warning: throwing CSerialException for error %d\n"), dwError); #ifdef CSERIALPORT_MFC_EXTENSIONS CSerialException* pException = new CSerialException(dwError); THROW(pException); #else CSerialException e(dwError); throw e; #endif //#ifdef CSERIALPORT_MFC_EXTENSIONS } #ifdef CSERIALPORT_MFC_EXTENSIONS #ifdef _DEBUG void CSerialPort::Dump(CDumpContext& dc) const { dc << _T("m_hComm = ") << m_hComm << _T("\n"); } #endif //#ifdef _DEBUG #endif //#ifdef CSERIALPORT_MFC_EXTENSIONS void CSerialPort::Open(_In_z_ LPCTSTR pszPort, _In_ DWORD dwBaud, _In_ Parity parity, _In_ BYTE DataBits, _In_ StopBits stopBits, _In_ FlowControl fc, _In_ BOOL bOverlapped) { Close(); //In case we are already open //Call CreateFile to open the comms port m_hComm = CreateFile(pszPort, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, bOverlapped ? (FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED) : 0, NULL); if (m_hComm == INVALID_HANDLE_VALUE) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::Open, Failed to open the comms port, Error:%u\n"), dwLastError); //ThrowSerialException(dwLastError); return; } //Get the current state prior to changing it DCB dcb; dcb.DCBlength = sizeof(DCB); GetState(dcb); //Setup the baud rate dcb.BaudRate = dwBaud; //Setup the Parity switch (parity) { case EvenParity: { dcb.Parity = EVENPARITY; break; } case MarkParity: { dcb.Parity = MARKPARITY; break; } case NoParity: { dcb.Parity = NOPARITY; break; } case OddParity: { dcb.Parity = ODDPARITY; break; } case SpaceParity: { dcb.Parity = SPACEPARITY; break; } default: { ATLASSERT(FALSE); break; } } //Setup the data bits dcb.ByteSize = DataBits; //Setup the stop bits switch (stopBits) { case OneStopBit: { dcb.StopBits = ONESTOPBIT; break; } case OnePointFiveStopBits: { dcb.StopBits = ONE5STOPBITS; break; } case TwoStopBits: { dcb.StopBits = TWOSTOPBITS; break; } default: { ATLASSERT(FALSE); break; } } //Setup the flow control dcb.fDsrSensitivity = FALSE; switch (fc) { case NoFlowControl: { dcb.fOutxCtsFlow = FALSE; dcb.fOutxDsrFlow = FALSE; dcb.fOutX = FALSE; dcb.fInX = FALSE; break; } case CtsRtsFlowControl: { dcb.fOutxCtsFlow = TRUE; dcb.fOutxDsrFlow = FALSE; dcb.fRtsControl = RTS_CONTROL_HANDSHAKE; dcb.fOutX = FALSE; dcb.fInX = FALSE; break; } case CtsDtrFlowControl: { dcb.fOutxCtsFlow = TRUE; dcb.fOutxDsrFlow = FALSE; dcb.fDtrControl = DTR_CONTROL_HANDSHAKE; dcb.fOutX = FALSE; dcb.fInX = FALSE; break; } case DsrRtsFlowControl: { dcb.fOutxCtsFlow = FALSE; dcb.fOutxDsrFlow = TRUE; dcb.fRtsControl = RTS_CONTROL_HANDSHAKE; dcb.fOutX = FALSE; dcb.fInX = FALSE; break; } case DsrDtrFlowControl: { dcb.fOutxCtsFlow = FALSE; dcb.fOutxDsrFlow = TRUE; dcb.fDtrControl = DTR_CONTROL_HANDSHAKE; dcb.fOutX = FALSE; dcb.fInX = FALSE; break; } case XonXoffFlowControl: { dcb.fOutxCtsFlow = FALSE; dcb.fOutxDsrFlow = FALSE; dcb.fOutX = TRUE; dcb.fInX = TRUE; dcb.XonChar = 0x11; dcb.XoffChar = 0x13; dcb.XoffLim = 100; dcb.XonLim = 100; break; } default: { ATLASSERT(FALSE); break; } } //Now that we have all the settings in place, make the changes SetState(dcb); } void CSerialPort::Open(_In_ int nPort, _In_ DWORD dwBaud, _In_ Parity parity, _In_ BYTE DataBits, _In_ StopBits stopBits, _In_ FlowControl fc, _In_ BOOL bOverlapped) { //Form the string version of the port number TCHAR szPort[12]; _stprintf_s(szPort, sizeof(szPort) / sizeof(TCHAR), _T("\\\\.\\COM%d"), nPort); //Delegate the work to the other version of Open Open(szPort, dwBaud, parity, DataBits, stopBits, fc, bOverlapped); } void CSerialPort::Close() { if (IsOpen()) { //Close down the comms port CloseHandle(m_hComm); m_hComm = INVALID_HANDLE_VALUE; } } void CSerialPort::Attach(_In_ HANDLE hComm) { Close(); //Validate our parameters, now that the port has been closed ATLASSERT(m_hComm == INVALID_HANDLE_VALUE); m_hComm = hComm; } HANDLE CSerialPort::Detach() { //What will be the return value from this function HANDLE hComm = m_hComm; m_hComm = INVALID_HANDLE_VALUE; return hComm; } void CSerialPort::Read(_Out_writes_bytes_(dwNumberOfBytesToRead) __out_data_source(FILE) void* lpBuffer, _In_ DWORD dwNumberOfBytesToRead) { //Validate our parameters ATLASSERT(IsOpen()); DWORD dwBytesRead = 0; if (!ReadFile(m_hComm, lpBuffer, dwNumberOfBytesToRead, &dwBytesRead, NULL)) { DWORD dwLastError = GetLastError(); if (ERROR_IO_PENDING != dwLastError) ATLTRACE(_T("CSerialPort::Read, Failed in call to ReadFile, Error:%u\n"), dwLastError); // ThrowSerialException(dwLastError); } } void CSerialPort::Read(_Out_writes_bytes_to_opt_(dwNumberOfBytesToRead, *lpNumberOfBytesRead) __out_data_source(FILE) void* lpBuffer, _In_ DWORD dwNumberOfBytesToRead, _In_ OVERLAPPED& overlapped, _Inout_opt_ DWORD* lpNumberOfBytesRead) { //Validate our parameters ATLASSERT(IsOpen()); *lpNumberOfBytesRead = 0; if (overlapped.hEvent) ResetEvent(overlapped.hEvent); if (!ReadFile(m_hComm, lpBuffer, dwNumberOfBytesToRead, lpNumberOfBytesRead, &overlapped)) { DWORD dwLastError = GetLastError(); if (ERROR_IO_PENDING != dwLastError) { ATLTRACE(_T("CSerialPort::Read, Failed in call to ReadFile, Error:%u\n"), dwLastError); } // ThrowSerialException(dwLastError); } } void CSerialPort::ReadEx(_Out_writes_bytes_opt_(dwNumberOfBytesToRead) __out_data_source(FILE) LPVOID lpBuffer, _In_ DWORD dwNumberOfBytesToRead, _Inout_ LPOVERLAPPED lpOverlapped, _In_ LPOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine) { //Validate our parameters ATLASSERT(IsOpen()); if (!ReadFileEx(m_hComm, lpBuffer, dwNumberOfBytesToRead, lpOverlapped, lpCompletionRoutine)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::ReadEx, Failed in call to ReadFileEx, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } DWORD CSerialPort::Write(_In_reads_bytes_opt_(dwNumberOfBytesToWrite) const void* lpBuffer, _In_ DWORD dwNumberOfBytesToWrite) { //Validate our parameters ATLASSERT(IsOpen()); DWORD dwBytesWritten = 0; if (!WriteFile(m_hComm, lpBuffer, dwNumberOfBytesToWrite, &dwBytesWritten, NULL)) { DWORD dwLastError = GetLastError(); if (ERROR_IO_PENDING != dwLastError) ATLTRACE(_T("CSerialPort::Write, Failed in call to WriteFile, Error:%u\n"), dwLastError); //ThrowSerialException(dwLastError); } return dwBytesWritten; } void CSerialPort::Write(_In_reads_bytes_opt_(dwNumberOfBytesToWrite) const void* lpBuffer, _In_ DWORD dwNumberOfBytesToWrite, _In_ OVERLAPPED& overlapped, _Out_opt_ DWORD* lpNumberOfBytesWritten) { //Validate our parameters ATLASSERT(IsOpen()); if (!WriteFile(m_hComm, lpBuffer, dwNumberOfBytesToWrite, lpNumberOfBytesWritten, &overlapped)) { DWORD dwLastError = GetLastError(); if (ERROR_IO_PENDING != dwLastError) { ATLTRACE(_T("CSerialPort::Write, Failed in call to WriteFile, Error:%u\n"), dwLastError); } // ThrowSerialException(dwLastError); } } void CSerialPort::WriteEx(_In_reads_bytes_opt_(dwNumberOfBytesToWrite) LPCVOID lpBuffer, _In_ DWORD dwNumberOfBytesToWrite, _Inout_ LPOVERLAPPED lpOverlapped, _In_ LPOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine) { //Validate our parameters ATLASSERT(IsOpen()); if (!WriteFileEx(m_hComm, lpBuffer, dwNumberOfBytesToWrite, lpOverlapped, lpCompletionRoutine)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::WriteEx, Failed in call to WriteFileEx, Error:%u\n"), dwLastError); //ThrowSerialException(dwLastError); } } DWORD CSerialPort::GetOverlappedResult(_In_ OVERLAPPED& overlapped, _Out_ DWORD& dwBytesTransferred, _In_ BOOL bWait) { //Validate our parameters DWORD dwLastError = 0; ATLASSERT(IsOpen()); dwBytesTransferred = 0; if (!::GetOverlappedResult(m_hComm, &overlapped, &dwBytesTransferred, bWait)) { dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::GetOverlappedResult, Failed in call to GetOverlappedResult, Error:%u\n"), dwLastError); //ThrowSerialException(dwLastError); } return dwLastError; } void CSerialPort::CancelIo() { //Validate our parameters ATLASSERT(IsOpen()); if (!::CancelIo(m_hComm)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("Failed in call to CancelIO, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } DWORD CSerialPort::BytesWaiting() { //Validate our parameters //ATLASSERT(IsOpen()); if (!IsOpen()) return 0; //Check to see how many characters are unread COMSTAT stat; GetStatus(stat); return stat.cbInQue; } DWORD CSerialPort::BytesPending() { if (!IsOpen()) return 0; //Check to see how many characters are unwrite COMSTAT stat; GetStatus(stat); return stat.cbOutQue; } void CSerialPort::TransmitChar(_In_ char cChar) { //Validate our parameters ATLASSERT(IsOpen()); if (!TransmitCommChar(m_hComm, cChar)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::TransmitChar, Failed in call to TransmitCommChar, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::GetConfig(_In_ COMMCONFIG& config) { //Validate our parameters ATLASSERT(IsOpen()); DWORD dwSize = sizeof(COMMCONFIG); if (!GetCommConfig(m_hComm, &config, &dwSize)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::GetConfig, Failed in call to GetCommConfig, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::SetConfig(_In_ COMMCONFIG& config) { //Validate our parameters ATLASSERT(IsOpen()); DWORD dwSize = sizeof(COMMCONFIG); if (!SetCommConfig(m_hComm, &config, dwSize)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::SetConfig, Failed in call to SetCommConfig, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::SetBreak() { //Validate our parameters ATLASSERT(IsOpen()); if (!SetCommBreak(m_hComm)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::SetBreak, Failed in call to SetCommBreak, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::ClearBreak() { //Validate our parameters ATLASSERT(IsOpen()); if (!ClearCommBreak(m_hComm)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::ClearBreak, Failed in call to SetCommBreak, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::ClearError(_Out_ DWORD& dwErrors) { //Validate our parameters ATLASSERT(IsOpen()); if (!ClearCommError(m_hComm, &dwErrors, NULL)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::ClearError, Failed in call to ClearCommError, Error:%u\n"), dwLastError); //ThrowSerialException(dwLastError); } } void CSerialPort::GetDefaultConfig(_In_ int nPort, _Out_ COMMCONFIG& config) { //Create the device name as a string TCHAR szPort[12]; _stprintf_s(szPort, sizeof(szPort) / sizeof(TCHAR), _T("COM%d"), nPort); return GetDefaultConfig(szPort, config); } void CSerialPort::GetDefaultConfig(_In_z_ LPCTSTR pszPort, _Out_ COMMCONFIG& config) { DWORD dwSize = sizeof(COMMCONFIG); if (!GetDefaultCommConfig(pszPort, &config, &dwSize)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::GetDefaultConfig, Failed in call to GetDefaultCommConfig, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::SetDefaultConfig(_In_ int nPort, _In_ COMMCONFIG& config) { //Create the device name as a string TCHAR szPort[12]; _stprintf_s(szPort, sizeof(szPort) / sizeof(TCHAR), _T("COM%d"), nPort); return SetDefaultConfig(szPort, config); } void CSerialPort::SetDefaultConfig(_In_z_ LPCTSTR pszPort, _In_ COMMCONFIG& config) { DWORD dwSize = sizeof(COMMCONFIG); if (!SetDefaultCommConfig(pszPort, &config, dwSize)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::SetDefaultConfig, Failed in call to SetDefaultCommConfig, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::GetStatus(_Out_ COMSTAT& stat) { //Validate our parameters ATLASSERT(IsOpen()); DWORD dwErrors; if (!ClearCommError(m_hComm, &dwErrors, &stat)) { DWORD dwLastError = GetLastError(); stat.cbInQue = 0; ATLTRACE(_T("CSerialPort::GetStatus, Failed in call to ClearCommError, Error:%u\n"), dwLastError); // ThrowSerialException(dwLastError); } } void CSerialPort::GetState(_Out_ DCB& dcb) { //Validate our parameters ATLASSERT(IsOpen()); if (!GetCommState(m_hComm, &dcb)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::GetState, Failed in call to GetCommState, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::SetState(_In_ DCB& dcb) { //Validate our parameters ATLASSERT(IsOpen()); if (!SetCommState(m_hComm, &dcb)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::SetState, Failed in call to SetCommState, Error:%u\n"), dwLastError); // ThrowSerialException(dwLastError); } } void CSerialPort::Escape(_In_ DWORD dwFunc) { //Validate our parameters ATLASSERT(IsOpen()); if (!EscapeCommFunction(m_hComm, dwFunc)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::Escape, Failed in call to EscapeCommFunction, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::ClearDTR() { Escape(CLRDTR); } void CSerialPort::ClearRTS() { Escape(CLRRTS); } void CSerialPort::SetDTR() { Escape(SETDTR); } void CSerialPort::SetRTS() { Escape(SETRTS); } void CSerialPort::SetXOFF() { Escape(SETXOFF); } void CSerialPort::SetXON() { Escape(SETXON); } void CSerialPort::GetProperties(_Inout_ COMMPROP& properties) { //Validate our parameters ATLASSERT(IsOpen()); if (!GetCommProperties(m_hComm, &properties)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::GetProperties, Failed in call to GetCommProperties, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::GetModemStatus(_Out_ DWORD& dwModemStatus) { //Validate our parameters ATLASSERT(IsOpen()); if (!GetCommModemStatus(m_hComm, &dwModemStatus)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::GetModemStatus, Failed in call to GetCommModemStatus, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::SetMask(_In_ DWORD dwMask) { //Validate our parameters ATLASSERT(IsOpen()); if (!SetCommMask(m_hComm, dwMask)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::SetMask, Failed in call to SetCommMask, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::GetMask(_Out_ DWORD& dwMask) { //Validate our parameters ATLASSERT(IsOpen()); if (!GetCommMask(m_hComm, &dwMask)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::GetMask, Failed in call to GetCommMask, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::Flush() { //Validate our parameters ATLASSERT(IsOpen()); if (!FlushFileBuffers(m_hComm)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::Flush, Failed in call to FlushFileBuffers, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::Purge(_In_ DWORD dwFlags) { //Validate our parameters ATLASSERT(IsOpen()); if (!PurgeComm(m_hComm, dwFlags)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::Purge, Failed in call to PurgeComm, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::TerminateOutstandingWrites() { Purge(PURGE_TXABORT); } void CSerialPort::TerminateOutstandingReads() { Purge(PURGE_RXABORT); } void CSerialPort::ClearWriteBuffer() { Purge(PURGE_TXCLEAR); } void CSerialPort::ClearReadBuffer() { Purge(PURGE_RXCLEAR); } void CSerialPort::Setup(_In_ DWORD dwInQueue, _In_ DWORD dwOutQueue) { //Validate our parameters ATLASSERT(IsOpen()); if (!SetupComm(m_hComm, dwInQueue, dwOutQueue)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::Setup, Failed in call to SetupComm, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::SetTimeouts(_In_ COMMTIMEOUTS& timeouts) { //Validate our parameters ATLASSERT(IsOpen()); if (!SetCommTimeouts(m_hComm, &timeouts)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::SetTimeouts, Failed in call to SetCommTimeouts, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::GetTimeouts(_Out_ COMMTIMEOUTS& timeouts) { //Validate our parameters ATLASSERT(IsOpen()); if (!GetCommTimeouts(m_hComm, &timeouts)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::GetTimeouts, Failed in call to GetCommTimeouts, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } void CSerialPort::Set0Timeout() { COMMTIMEOUTS Timeouts; memset(&Timeouts, 0, sizeof(Timeouts)); Timeouts.ReadIntervalTimeout = MAXDWORD; SetTimeouts(Timeouts); } void CSerialPort::Set0WriteTimeout() { COMMTIMEOUTS Timeouts; GetTimeouts(Timeouts); Timeouts.WriteTotalTimeoutMultiplier = 0; Timeouts.WriteTotalTimeoutConstant = 0; SetTimeouts(Timeouts); } void CSerialPort::Set0ReadTimeout() { COMMTIMEOUTS Timeouts; GetTimeouts(Timeouts); Timeouts.ReadIntervalTimeout = MAXDWORD; Timeouts.ReadTotalTimeoutMultiplier = 0; Timeouts.ReadTotalTimeoutConstant = 0; SetTimeouts(Timeouts); } void CSerialPort::WaitEvent(_Inout_ DWORD& dwMask) { //Validate our parameters ATLASSERT(IsOpen()); if (!WaitCommEvent(m_hComm, &dwMask, NULL)) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::WaitEvent, Failed in call to WaitCommEvent, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } } BOOL CSerialPort::WaitEvent(_Inout_ DWORD& dwMask, _Inout_ OVERLAPPED& overlapped) { //Validate our parameters ATLASSERT(IsOpen()); ATLASSERT(overlapped.hEvent != NULL); BOOL bSuccess = WaitCommEvent(m_hComm, &dwMask, &overlapped); if (!bSuccess) { DWORD dwLastError = GetLastError(); ATLTRACE(_T("CSerialPort::WaitEvent, Failed in call to WaitCommEvent, Error:%u\n"), dwLastError); ThrowSerialException(dwLastError); } return bSuccess; } #pragma once #include "afxwin.h" // 自定义串口异常类 class CSerialException : public CException { public: DWORD m_dwError; CSerialException(DWORD dwError); }; // 串口类声明 class CSerialPort { public: enum Parity { None, Odd, Even }; enum StopBits { One = 1, OnePointFive = 2, Two = 3 }; CSerialPort(); virtual ~CSerialPort(); // 添加 virtual 关键字 BOOL Open(LPCTSTR lpszPort, DWORD dwBaudRate, Parity parity, BYTE byDataBits, StopBits stopBits); void Close(); BOOL IsOpen() const { return m_hComm != INVALID_HANDLE_VALUE; } DWORD Write(const void* lpBuf, DWORD dwCount); DWORD Read(void* lpBuf, DWORD dwCount); DWORD BytesWaiting(); void Set0Timeout(); private: HANDLE m_hComm; }; // CPCMFCDlg 对话框 class CPCMFCDlg : public CDialogEx { public: CPCMFCDlg(CWnd* pParent = nullptr); virtual ~CPCMFCDlg(); #ifdef AFX_DESIGN_TIME enum { IDD = IDD_PCMFC_DIALOG }; #endif protected: virtual void DoDataExchange(CDataExchange* pDX); virtual BOOL OnInitDialog(); protected: HICON m_hIcon; // 控件变量 CComboBox m_cbPort; CComboBox m_cbBaud; CComboBox m_cbParity; CComboBox m_cbDate; CComboBox m_cbStop; CListBox m_listStatus; // 数据变量 CString m_strTime1; CString m_strTime2; CString m_strTime3; // 状态变量 BOOL m_bConnected; BOOL m_bTimerActive; BOOL m_bThreadRunning; // 串口对象 CSerialPort m_SerialPort; HANDLE m_hThread; // 辅助函数 void UpdateControls(); UINT ReadThreadFunc(); static UINT ReadThread(LPVOID pParam); BOOL ValidateTimeFormat(const CString& strTime); // 消息处理 DECLARE_MESSAGE_MAP() afx_msg void OnPaint(); afx_msg HCURSOR OnQueryDragIcon(); afx_msg void OnBnClickedBtnOpen(); afx_msg void OnBnClickedBtnClose(); afx_msg void OnBnClickedBtnFeedNow(); afx_msg void OnBnClickedBtnFeedTimer(); afx_msg LRESULT OnUpdateStatus(WPARAM wParam, LPARAM lParam); afx_msg void OnTimer(UINT_PTR nIDEvent); afx_msg void OnDestroy(); }; #include "pch.h" #include "PCMFC.h" #include "PCMFCDlg.h" #include "afxdialogex.h" #include <winbase.h> #include <tchar.h> #include <atlstr.h> #ifdef _DEBUG #define new DEBUG_NEW #endif #define FEED_COMMAND 0x01 #define COMPLETE_SIGNAL 0xFF #define WM_UPDATE_STATUS (WM_USER + 100) // CSerialException 实现 CSerialException::CSerialException(DWORD dwError) : m_dwError(dwError) {} // CSerialPort 成员函数实现 CSerialPort::CSerialPort() : m_hComm(INVALID_HANDLE_VALUE) {} CSerialPort::~CSerialPort() { if (IsOpen()) Close(); } BOOL CSerialPort::Open(LPCTSTR lpszPort, DWORD dwBaudRate, Parity parity, BYTE byDataBits, StopBits stopBits) { m_hComm = CreateFile(lpszPort, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, FILE_FLAG_OVERLAPPED, NULL); if (m_hComm == INVALID_HANDLE_VALUE) throw new CSerialException(GetLastError()); DCB dcb = { 0 }; dcb.DCBlength = sizeof(DCB); if (!GetCommState(m_hComm, &dcb)) throw new CSerialException(GetLastError()); dcb.BaudRate = dwBaudRate; dcb.ByteSize = byDataBits; switch (parity) { case None: dcb.Parity = NOPARITY; break; case Odd: dcb.Parity = ODDPARITY; break; case Even: dcb.Parity = EVENPARITY; break; } switch (stopBits) { case One: dcb.StopBits = ONESTOPBIT; break; case OnePointFive: dcb.StopBits = ONE5STOPBITS; break; case Two: dcb.StopBits = TWOSTOPBITS; break; } dcb.fBinary = TRUE; dcb.fDtrControl = DTR_CONTROL_ENABLE; dcb.fRtsControl = RTS_CONTROL_ENABLE; if (!SetCommState(m_hComm, &dcb)) throw new CSerialException(GetLastError()); // 设置超时 COMMTIMEOUTS timeouts = { 0 }; timeouts.ReadIntervalTimeout = 50; timeouts.ReadTotalTimeoutConstant = 50; timeouts.ReadTotalTimeoutMultiplier = 10; timeouts.WriteTotalTimeoutConstant = 50; timeouts.WriteTotalTimeoutMultiplier = 10; if (!SetCommTimeouts(m_hComm, &timeouts)) throw new CSerialException(GetLastError()); return TRUE; } void CSerialPort::Close() { if (m_hComm != INVALID_HANDLE_VALUE) { CloseHandle(m_hComm); m_hComm = INVALID_HANDLE_VALUE; } } DWORD CSerialPort::Write(const void* lpBuf, DWORD dwCount) { DWORD dwBytesWritten = 0; OVERLAPPED ov = { 0 }; ov.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL); if (!WriteFile(m_hComm, lpBuf, dwCount, &dwBytesWritten, &ov)) { if (GetLastError() == ERROR_IO_PENDING) { WaitForSingleObject(ov.hEvent, INFINITE); GetOverlappedResult(m_hComm, &ov, &dwBytesWritten, FALSE); } else { throw new CSerialException(GetLastError()); } } CloseHandle(ov.hEvent); return dwBytesWritten; } DWORD CSerialPort::Read(void* lpBuf, DWORD dwCount) { DWORD dwBytesRead = 0; OVERLAPPED ov = { 0 }; ov.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL); if (!ReadFile(m_hComm, lpBuf, dwCount, &dwBytesRead, &ov)) { if (GetLastError() == ERROR_IO_PENDING) { WaitForSingleObject(ov.hEvent, INFINITE); GetOverlappedResult(m_hComm, &ov, &dwBytesRead, FALSE); } else { throw new CSerialException(GetLastError()); } } CloseHandle(ov.hEvent); return dwBytesRead; } DWORD CSerialPort::BytesWaiting() { COMSTAT comStat; DWORD dwErrors; if (!ClearCommError(m_hComm, &dwErrors, &comStat)) throw new CSerialException(GetLastError()); return comStat.cbInQue; } void CSerialPort::Set0Timeout() { COMMTIMEOUTS timeouts = { 0 }; timeouts.ReadIntervalTimeout = MAXDWORD; timeouts.ReadTotalTimeoutConstant = 0; timeouts.ReadTotalTimeoutMultiplier = 0; timeouts.WriteTotalTimeoutMultiplier = 0; timeouts.WriteTotalTimeoutConstant = 0; if (!SetCommTimeouts(m_hComm, &timeouts)) throw new CSerialException(GetLastError()); } // CPCMFCDlg 实现 CPCMFCDlg::CPCMFCDlg(CWnd* pParent) : CDialogEx(IDD_PCMFC_DIALOG, pParent) , m_strTime1(_T("08:00")) , m_strTime2(_T("12:00")) , m_strTime3(_T("18:00")) , m_bConnected(FALSE) , m_bTimerActive(FALSE) , m_bThreadRunning(FALSE) , m_hThread(NULL) { m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME); } CPCMFCDlg::~CPCMFCDlg() { if (m_hThread) { CloseHandle(m_hThread); } } void CPCMFCDlg::DoDataExchange(CDataExchange* pDX) { CDialogEx::DoDataExchange(pDX); DDX_Control(pDX, IDC_COMBO_PORT, m_cbPort); DDX_Control(pDX, IDC_COMBO_BAUD, m_cbBaud); DDX_Control(pDX, IDC_COMBO_PARITY, m_cbParity); DDX_Control(pDX, IDC_COMBO_DATA, m_cbDate); DDX_Control(pDX, IDC_COMBO_STOP, m_cbStop); DDX_Control(pDX, IDC_LIST, m_listStatus); DDX_Text(pDX, IDC_EDIT_TIME1, m_strTime1); DDX_Text(pDX, IDC_EDIT_TIME2, m_strTime2); DDX_Text(pDX, IDC_EDIT_TIME3, m_strTime3); } BEGIN_MESSAGE_MAP(CPCMFCDlg, CDialogEx) ON_WM_PAINT() ON_WM_QUERYDRAGICON() ON_BN_CLICKED(IDC_BUTTON_OPEN, &CPCMFCDlg::OnBnClickedBtnOpen) ON_BN_CLICKED(IDC_BUTTON_CLOSE, &CPCMFCDlg::OnBnClickedBtnClose) ON_BN_CLICKED(IDC_BUTTON_NOWFEED, &CPCMFCDlg::OnBnClickedBtnFeedNow) ON_BN_CLICKED(IDC_BUTTON_TIMEFEED, &CPCMFCDlg::OnBnClickedBtnFeedTimer) ON_MESSAGE(WM_UPDATE_STATUS, &CPCMFCDlg::OnUpdateStatus) ON_WM_TIMER() ON_WM_DESTROY() END_MESSAGE_MAP() BOOL CPCMFCDlg::OnInitDialog() { CDialogEx::OnInitDialog(); SetIcon(m_hIcon, TRUE); SetIcon(m_hIcon, FALSE); // 初始化串口选择下拉框 for (int i = 1; i <= 16; i++) { CString port; port.Format(_T("COM%d"), i); m_cbPort.AddString(port); } m_cbPort.SetCurSel(0); // 初始化波特率下拉框 CString baudRates[] = { _T("9600"), _T("19200"), _T("38400"), _T("57600"), _T("115200") }; for (auto& baud : baudRates) { m_cbBaud.AddString(baud); } m_cbBaud.SetCurSel(0); // 初始化校验位下拉框 CString parityOptions[] = { _T("None"), _T("Odd"), _T("Even") }; for (auto& parity : parityOptions) { m_cbParity.AddString(parity); } m_cbParity.SetCurSel(0); // 初始化数据位下拉框 CString dataBits[] = { _T("5"), _T("6"), _T("7"), _T("8") }; for (auto& bits : dataBits) { m_cbDate.AddString(bits); } m_cbDate.SetCurSel(3); // 初始化停止位下拉框 CString stopBits[] = { _T("1"), _T("1.5"), _T("2") }; for (auto& stop : stopBits) { m_cbStop.AddString(stop); } m_cbStop.SetCurSel(0); // 初始禁用控件 UpdateControls(); return TRUE; } void CPCMFCDlg::UpdateControls() { BOOL bConnected = m_SerialPort.IsOpen(); GetDlgItem(IDC_BUTTON_OPEN)->EnableWindow(!bConnected); GetDlgItem(IDC_BUTTON_CLOSE)->EnableWindow(bConnected); GetDlgItem(IDC_BUTTON_NOWFEED)->EnableWindow(bConnected); GetDlgItem(IDC_BUTTON_TIMEFEED)->EnableWindow(bConnected); BOOL bTimerActive = m_bTimerActive; GetDlgItem(IDC_EDIT_TIME1)->EnableWindow(bConnected && !bTimerActive); GetDlgItem(IDC_EDIT_TIME2)->EnableWindow(bConnected && !bTimerActive); GetDlgItem(IDC_EDIT_TIME3)->EnableWindow(bConnected && !bTimerActive); } BOOL CPCMFCDlg::ValidateTimeFormat(const CString& strTime) { if (strTime.GetLength() != 5) return FALSE; if (strTime[2] != ':') return FALSE; int hour = _ttoi(strTime.Left(2)); int minute = _ttoi(strTime.Mid(3)); return (hour >= 0 && hour <= 23) && (minute >= 0 && minute <= 59); } UINT CPCMFCDlg::ReadThread(LPVOID pParam) { CPCMFCDlg* pDlg = (CPCMFCDlg*)pParam; return pDlg->ReadThreadFunc(); } UINT CPCMFCDlg::ReadThreadFunc() { BYTE buffer[1]; while (m_bThreadRunning) { try { DWORD dwBytes = m_SerialPort.BytesWaiting(); if (dwBytes > 0) { if (m_SerialPort.Read(buffer, 1) > 0) { if (buffer[0] == COMPLETE_SIGNAL) { CString* pMsg = new CString(_T("喂食操作完成")); PostMessage(WM_UPDATE_STATUS, (WPARAM)pMsg, 0); } } } Sleep(50); } catch (CSerialException* e) { CString* pMsg = new CString(); pMsg->Format(_T("串口读取错误: %d"), e->m_dwError); PostMessage(WM_UPDATE_STATUS, (WPARAM)pMsg, 0); delete e; break; } } return 0; } void CPCMFCDlg::OnBnClickedBtnOpen() { CString strPort; m_cbPort.GetWindowText(strPort); strPort = _T("\\\\.\\") + strPort; CString strBaud; m_cbBaud.GetLBText(m_cbBaud.GetCurSel(), strBaud); DWORD dwBaud = _ttoi(strBaud); int nParity = m_cbParity.GetCurSel(); CString strDataBits; m_cbDate.GetLBText(m_cbDate.GetCurSel(), strDataBits); BYTE byDataBits = (BYTE)_ttoi(strDataBits); int nStopBits = m_cbStop.GetCurSel(); try { CSerialPort::Parity parity = static_cast<CSerialPort::Parity>(nParity); CSerialPort::StopBits stopBits = static_cast<CSerialPort::StopBits>(nStopBits); m_SerialPort.Open(strPort, dwBaud, parity, byDataBits, stopBits); m_SerialPort.Set0Timeout(); m_bConnected = TRUE; m_bThreadRunning = TRUE; m_hThread = (HANDLE)_beginthreadex(NULL, 0, ReadThread, this, 0, NULL); m_listStatus.AddString(_T("串口打开成功")); } catch (CSerialException* e) { CString strError; strError.Format(_T("打开串口失败: 错误代码 %d"), e->m_dwError); m_listStatus.AddString(strError); delete e; m_bConnected = FALSE; } UpdateControls(); } void CPCMFCDlg::OnBnClickedBtnClose() { m_bThreadRunning = FALSE; if (m_hThread) { WaitForSingleObject(m_hThread, 1000); CloseHandle(m_hThread); m_hThread = NULL; } try { if (m_SerialPort.IsOpen()) { m_SerialPort.Close(); m_listStatus.AddString(_T("串口已关闭")); } } catch (CSerialException* e) { delete e; } m_bConnected = FALSE; UpdateControls(); } void CPCMFCDlg::OnBnClickedBtnFeedNow() { BYTE cmd = FEED_COMMAND; try { if (m_SerialPort.IsOpen()) { m_SerialPort.Write(&cmd, 1); m_listStatus.AddString(_T("喂食命令已发送")); } } catch (CSerialException* e) { CString strError; strError.Format(_T("发送失败: 错误代码 %d"), e->m_dwError); m_listStatus.AddString(strError); delete e; } } void CPCMFCDlg::OnBnClickedBtnFeedTimer() { if (m_bTimerActive) { KillTimer(1); m_bTimerActive = FALSE; GetDlgItem(IDC_BUTTON_TIMEFEED)->SetWindowText(_T("开始定时")); m_listStatus.AddString(_T("定时器已停止")); } else { UpdateData(TRUE); // 验证时间格式 if (!ValidateTimeFormat(m_strTime1) || !ValidateTimeFormat(m_strTime2) || !ValidateTimeFormat(m_strTime3)) { MessageBox(_T("时间格式无效! 请使用HH:MM格式"), _T("错误"), MB_ICONERROR); return; } m_bTimerActive = TRUE; SetTimer(1, 1000, NULL); // 每秒检查一次 GetDlgItem(IDC_BUTTON_TIMEFEED)->SetWindowText(_T("停止定时")); m_listStatus.AddString(_T("定时器已启动")); } UpdateControls(); } void CPCMFCDlg::OnTimer(UINT_PTR nIDEvent) { if (nIDEvent == 1) { CTime now = CTime::GetCurrentTime(); CString strNow = now.Format(_T("%H:%M")); if (strNow == m_strTime1 || strNow == m_strTime2 || strNow == m_strTime3) { OnBnClickedBtnFeedNow(); } } CDialogEx::OnTimer(nIDEvent); } LRESULT CPCMFCDlg::OnUpdateStatus(WPARAM wParam, LPARAM lParam) { CString* pStr = (CString*)wParam; if (pStr) { m_listStatus.AddString(*pStr); delete pStr; } return 0; } void CPCMFCDlg::OnDestroy() { CDialogEx::OnDestroy(); if (m_bTimerActive) { KillTimer(1); } m_bThreadRunning = FALSE; if (m_hThread) { WaitForSingleObject(m_hThread, 1000); CloseHandle(m_hThread); m_hThread = NULL; } if (m_SerialPort.IsOpen()) { m_SerialPort.Close(); } } void CPCMFCDlg::OnPaint() { if (IsIconic()) { CPaintDC dc(this); SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0); int cxIcon = GetSystemMetrics(SM_CXICON); int cyIcon = GetSystemMetrics(SM_CYICON); CRect rect; GetClientRect(&rect); int x = (rect.Width() - cxIcon + 1) / 2; int y = (rect.Height() - cyIcon + 1) / 2; dc.DrawIcon(x, y, m_hIcon); } else { CDialogEx::OnPaint(); } } HCURSOR CPCMFCDlg::OnQueryDragIcon() { return static_cast<HCURSOR>(m_hIcon); } "public: void __cdecl CSerialPort::Set0Timeout(void)" (?Set0Timeout@CSerialPort@@QEAAXXZ) 已经在 PCMFCDlg.obj 中定义 "public: unsigned long __cdecl CSerialPort::BytesWaiting(void)" (?BytesWaiting@CSerialPort@@QEAAKXZ) 已经在 PCMFCDlg.obj 中定义 "public: unsigned long __cdecl CSerialPort::Write(void const *,unsigned long)" (?Write@CSerialPort@@QEAAKPEBXK@Z) 已经在 PCMFCDlg.obj 中定义 "public: void __cdecl CSerialPort::Close(void)" (?Close@CSerialPort@@QEAAXXZ) 已经在 PCMFCDlg.obj 中定义 "public: virtual __cdecl CSerialPort::~CSerialPort(void)" (??1CSerialPort@@UEAA@XZ) 已经在 PCMFCDlg.obj 中定义 "public: __cdecl CSerialPort::CSerialPort(void)" (??0CSerialPort@@QEAA@XZ) 已经在 PCMFCDlg.obj 中定义 "public: __cdecl CSerialException::CSerialException(unsigned long)" (??0CSerialException@@QEAA@K@Z) 已经在 PCMFCDlg.obj 中定义 找到一个或多个多重定义的符号 请你解决这些问题
06-04
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