求高手帮我看一下如何调用这段头文件中的C接口函数

[kkman7304]

#if defined(__cplusplus) && !defined(CINTERFACE)
    
    MIDL_INTERFACE("AFEA5514-AE9C-11D3-83AE-00A024BDBF2B")
    IActQJ71E71UDP : public IDispatch
    {
    public:
        virtual /* [helpstring][id] */ HRESULT STDMETHODCALLTYPE Open( 
            /* [retval][out] */ LONG __RPC_FAR *lplReturnCode) = 0;
        
        virtual /* [helpstring][id] */ HRESULT STDMETHODCALLTYPE Close( 
            /* [retval][out] */ LONG __RPC_FAR *lplReturnCode) = 0;
  
#else 	/* C style interface */

    typedef struct IActQJ71E71UDPVtbl
    {
        BEGIN_INTERFACE
        
        HRESULT ( STDMETHODCALLTYPE __RPC_FAR *QueryInterface )( 
            IActQJ71E71UDP __RPC_FAR * This,
            /* [in] */ REFIID riid,
            /* [iid_is][out] */ void __RPC_FAR *__RPC_FAR *ppvObject);
        
        ULONG ( STDMETHODCALLTYPE __RPC_FAR *AddRef )( 
            IActQJ71E71UDP __RPC_FAR * This);
        
        ULONG ( STDMETHODCALLTYPE __RPC_FAR *Release )( 
            IActQJ71E71UDP __RPC_FAR * This);
        
        HRESULT ( STDMETHODCALLTYPE __RPC_FAR *GetTypeInfoCount )( 
            IActQJ71E71UDP __RPC_FAR * This,
            /* [out] */ UINT __RPC_FAR *pctinfo);
        
        HRESULT ( STDMETHODCALLTYPE __RPC_FAR *GetTypeInfo )( 
            IActQJ71E71UDP __RPC_FAR * This,
            /* [in] */ UINT iTInfo,
            /* [in] */ LCID lcid,
            /* [out] */ ITypeInfo __RPC_FAR *__RPC_FAR *ppTInfo);
        
        HRESULT ( STDMETHODCALLTYPE __RPC_FAR *GetIDsOfNames )( 
            IActQJ71E71UDP __RPC_FAR * This,
            /* [in] */ REFIID riid,
            /* [size_is][in] */ LPOLESTR __RPC_FAR *rgszNames,
            /* [in] */ UINT cNames,
            /* [in] */ LCID lcid,
            /* [size_is][out] */ DISPID __RPC_FAR *rgDispId);
        
        /* [local] */ HRESULT ( STDMETHODCALLTYPE __RPC_FAR *Invoke )( 
            IActQJ71E71UDP __RPC_FAR * This,
            /* [in] */ DISPID dispIdMember,
            /* [in] */ REFIID riid,
            /* [in] */ LCID lcid,
            /* [in] */ WORD wFlags,
            /* [out][in] */ DISPPARAMS __RPC_FAR *pDispParams,
            /* [out] */ VARIANT __RPC_FAR *pVarResult,
            /* [out] */ EXCEPINFO __RPC_FAR *pExcepInfo,
            /* [out] */ UINT __RPC_FAR *puArgErr);
        
        /* [helpstring][id] */ HRESULT ( STDMETHODCALLTYPE __RPC_FAR *Open )( 
            IActQJ71E71UDP __RPC_FAR * This,
            /* [retval][out] */ LONG __RPC_FAR *lplReturnCode);
        
        /* [helpstring][id] */ HRESULT ( STDMETHODCALLTYPE __RPC_FAR *Close )( 
            IActQJ71E71UDP __RPC_FAR * This,
            /* [retval][out] */ LONG __RPC_FAR *lplReturnCode);
        
        END_INTERFACE
    } IActQJ71E71UDPVtbl;

    interface IActQJ71E71UDP
    {
        CONST_VTBL struct IActQJ71E71UDPVtbl __RPC_FAR *lpVtbl;
    };

        
    };
    

是关于三菱PLC的h头文件中的一段，给的dll库

[kkman7304]

#ifdef COBJMACROS


#define IActEasyIF_QueryInterface(This,riid,ppvObject)	\
    (This)->lpVtbl -> QueryInterface(This,riid,ppvObject)

#define IActEasyIF_AddRef(This)	\
    (This)->lpVtbl -> AddRef(This)

#define IActEasyIF_Release(This)	\
    (This)->lpVtbl -> Release(This)


#define IActEasyIF_GetTypeInfoCount(This,pctinfo)	\
    (This)->lpVtbl -> GetTypeInfoCount(This,pctinfo)

#define IActEasyIF_GetTypeInfo(This,iTInfo,lcid,ppTInfo)	\
    (This)->lpVtbl -> GetTypeInfo(This,iTInfo,lcid,ppTInfo)

#define IActEasyIF_GetIDsOfNames(This,riid,rgszNames,cNames,lcid,rgDispId)	\
    (This)->lpVtbl -> GetIDsOfNames(This,riid,rgszNames,cNames,lcid,rgDispId)

#define IActEasyIF_Invoke(This,dispIdMember,riid,lcid,wFlags,pDispParams,pVarResult,pExcepInfo,puArgErr)	\
    (This)->lpVtbl -> Invoke(This,dispIdMember,riid,lcid,wFlags,pDispParams,pVarResult,pExcepInfo,puArgErr)


#define IActEasyIF_get_ActLogicalStationNumber(This,pVal)	\
    (This)->lpVtbl -> get_ActLogicalStationNumber(This,pVal)

#define IActEasyIF_put_ActLogicalStationNumber(This,newVal)	\
    (This)->lpVtbl -> put_ActLogicalStationNumber(This,newVal)

#define IActEasyIF_Open(This,lplReturnCode)	\
    (This)->lpVtbl -> Open(This,lplReturnCode)

#define IActEasyIF_Close(This,lplReturnCode)	\
    (This)->lpVtbl -> Close(This,lplReturnCode)

[qq120848369]

头文件里有什么接口, 你就用什么, DLL这个东西除了要链接进来你也没必要费心其他的事情了.