idispatchimpl.h

《脚本驱动的应用软件开发方法与实践》源代码下载

//
// IDispatchImpl.h
//
// --------------------------------------------------------
// A Practical Guide to Script-Driven Software Development
// Author: Qiming Lu                        Date: 6/1/2006
// MSN Messager: [e-mail]
// MSN Blog: http://spaces.msn.com/jemylu
// --------------------------------------------------------

#ifndef __H_IDispatchImpl__
#define __H_IDispatchImpl__

template<class DERIVED_CLASS, class BASE_ITF, const IID* BASE_IID>
class IDispatchImpl : public BASE_ITF
{
protected:
	long			m_cRef;
	ITypeInfo*		m_pti;
	ITypeLib*		m_ptl;
	
public:
	IDispatchImpl() : m_pti(0), m_ptl(0), m_cRef(1) {};
	virtual ~IDispatchImpl(void) 
	{
		if (m_pti)
		{
			m_pti->Release();
			m_pti = 0;
		}
	}
	
	void LoadTypeInfo(ITypeLib* ptl)
	{
		// Note: we don't add extra reference to ptl!
		m_ptl = ptl;
		m_ptl->GetTypeInfoOfGuid(*BASE_IID, &m_pti);
	}

	// Note: NOT outstanding!
	ITypeInfo* GetTypeInfoInterface() {return m_pti;}

	// --- IUnknown methods --- 
	HRESULT STDMETHODCALLTYPE QueryInterface(REFIID riid, void **ppvObject) 
	{
		if (IID_IUnknown == riid)
		{
			*ppvObject = static_cast<IUnknown*> (this);
			AddRef();
			return S_OK;
		}
		else if (IID_IDispatch == riid)
		{
			*ppvObject = static_cast<IDispatch*> (this);
			AddRef();
			return S_OK;
		}
		else if (*BASE_IID == riid)
		{
			*ppvObject = static_cast<BASE_ITF*> (this);
			AddRef();
			return S_OK;
		}

		*ppvObject = 0;
		return E_NOINTERFACE;
	}

	ULONG STDMETHODCALLTYPE AddRef()
	{
		return InterlockedIncrement(&m_cRef);
	}

	ULONG STDMETHODCALLTYPE Release()
	{
		if (0 == InterlockedDecrement(&m_cRef))
		{
			delete this;
			return 0;
		}
		return m_cRef;
	}


	// --- IDispatch methods ---
	STDMETHODIMP GetTypeInfoCount(UINT * pctinfo)
	{			
		*pctinfo = 1;
		return S_OK;
	}	

	STDMETHODIMP GetTypeInfo(UINT itinfo, LCID /*lcid*/, ITypeInfo ** pptinfo)
	{
		if (0 == pptinfo)
		{
			return E_POINTER;
		}
		if (0 != itinfo)
		{
			return TYPE_E_ELEMENTNOTFOUND;
		}
		if (0 == m_pti)	
		{
			return TYPE_E_ELEMENTNOTFOUND;	
		}

		*pptinfo = m_pti;
		m_pti->AddRef();
		return S_OK;
	}			

	STDMETHODIMP GetIDsOfNames(REFIID /*riid*/,	
		OLECHAR  ** rgszNames,
		UINT cNames,
		LCID /*lcid*/,
		DISPID * rgdispid)	
	{
		return m_pti->GetIDsOfNames(rgszNames, cNames, rgdispid);
	}	

	STDMETHODIMP Invoke(DISPID dispidMember,
		REFIID riid,
		LCID /*lcid*/,	
		WORD wFlags,
		DISPPARAMS * pdispparams,
		VARIANT * pvarResult,	
		EXCEPINFO * pexcepinfo,
		UINT * puArgErr)
	{
		if (IID_NULL != riid)
		{
			return DISP_E_UNKNOWNINTERFACE;	
		}	

		HRESULT hr = NOERROR;
		try
		{
			hr = m_pti->Invoke((void*) this, dispidMember, wFlags,
				pdispparams, pvarResult, pexcepinfo, puArgErr);
		}
		catch (...)
		{
			hr = E_UNEXPECTED;
		}

		return hr;
	}
};

#endif	//__H_IDispatchImpl__