stcomerror.h

windows ce开发技巧与实例光盘代码

#if !defined(AFX_STUTIL_H__C403F6AF_B3FA_4BDA_A15F_7DA68EB6E3BF__INCLUDED_)
#define AFX_STUTIL_H__C403F6AF_B3FA_4BDA_A15F_7DA68EB6E3BF__INCLUDED_

#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000




/////////////////////////////////////////////////////////////////////////////
// The CSTComError class encapsulates the HRESULT error code.

class CSTComError
{
public:
	// Default constructor creates object that encapsulates S_OK code
	CSTComError();

	// Default object that encapsulates the given error code
	CSTComError(HRESULT hrError);

	// Copy constructor. 
	CSTComError(const CSTComError &src);

	// Assignes information about COM error
	CSTComError& operator=(const CSTComError &src);

	// Raw HRESULT item passed into the constructor.
	HRESULT Error() const;

private:
	HRESULT m_hrError;
};

// Returns information about the last COM error
CSTComError GetComError();

extern CSTComError lastComError;


/////////////////////////////////////////////////////////////////////////////
// Functions and macros for handling COM error without C++ exceptions (these
// exceptions are not implemented in eVC).

// Code of the exception that will be thrown in case of
// COM error HRESULT.
#define EXCEPTION_COMERROR 4549 

// Definition of standard function that is used by smart 
// pointers to report about error HRESULT code. This function
// throws exception using RaiseException function. This 
// exception could be catched using 
// __except (CATCH_COM_ERROR)
// code. If ST_IGNORE_COM_EXCEPTIONS is defined this function
// does nothing (no exception is thrown).
extern void __stdcall _com_issue_error(HRESULT hResult);

// Definition of standard function that is used by smart 
// pointers to report about error HRESULT code. This function
// throws exception using RaiseException function. This 
// exception could be catched using 
// __except (CATCH_COM_ERROR)
// code. If ST_IGNORE_COM_EXCEPTIONS is defined this function
// does nothing (no exception is thrown).
extern void __stdcall _com_issue_errorex(HRESULT hResult, IUnknown* pUnknown, REFIID refid);

// Checks whether the exception corresponds to COM error or
// not and fill lastComError variable with information about
// COM error. This function should be called from __except.
// Returns true is dwCode equals 
extern int ComErrorFilterFunction(DWORD dwCode, LPEXCEPTION_POINTERS info);

// This macro represents right calling of ComErrorFilterFunction
// function from __except. Just write
// __except (CATCH_COM_ERROR)
// to catch COM error exceptions.
#define CATCH_COM_ERROR ComErrorFilterFunction(GetExceptionCode(), GetExceptionInformation())


#endif // !defined(AFX_STUTIL_H__C403F6AF_B3FA_4BDA_A15F_7DA68EB6E3BF__INCLUDED_)