发一个实用函数，word文件转换成文本文件(DocToTxt)

#include 
#include 

void DocToTxt(BSTR bstrOpenFile, BSTR bstrSaveFile);
void DocToTxt(BSTR bstrOpenFile, BSTR bstrSaveFile)
{
	// ******************* Declare Some Variables ********************

    // Variables that will be used and re-used in our calls
    DISPPARAMS		m_dpNoArgs = {NULL, NULL, 0, 0};
    VARIANT			m_vResult;
    OLECHAR FAR*	m_szFunction;

    // IDispatch pointers for Word's objects
    IDispatch*		m_pDispDocs;		  //Documents collection
    IDispatch*		m_pDispActiveDoc;	  //ActiveDocument object

    // DISPID's
    DISPID			m_dispid_Docs;        //Documents property of Application object
    DISPID			m_dispid_ActiveDoc;   //ActiveDocument property of Application 
    DISPID			m_dispid_SaveAs;      //SaveAs method of the Document object
    DISPID			m_dispid_Quit;        //Quit method of the Application object

	DISPID			m_dispid_Open;		  //Open method of the Application object
	BSTR			m_bstrEmptyString ;

    // ******************** Start Automation ***********************

    //Initialize the COM libraries
    ::CoInitialize(NULL);

    // Create an instance of the Word application and obtain the pointer
    // to the application's IDispatch interface.
    CLSID	m_clsid;
    CLSIDFromProgID(L"Word.Application", &m_clsid);

    IUnknown*	m_pUnk;
    HRESULT m_hr = ::CoCreateInstance( m_clsid, NULL, CLSCTX_SERVER,
                                       IID_IUnknown, (void**) &m_pUnk);
    IDispatch*	m_pDispApp;
    m_hr = m_pUnk->QueryInterface( IID_IDispatch, (void**)&m_pDispApp);

	// Get IDispatch* for the Documents collection object
    m_szFunction = OLESTR("Documents");
    m_hr = m_pDispApp->GetIDsOfNames (IID_NULL, &m_szFunction, 1, 
									  LOCALE_USER_DEFAULT, &m_dispid_Docs);
    m_hr = m_pDispApp->Invoke (m_dispid_Docs, IID_NULL, LOCALE_USER_DEFAULT,
							   DISPATCH_PROPERTYGET, &m_dpNoArgs, &m_vResult, 
							   NULL, NULL);
    m_pDispDocs = m_vResult.pdispVal;

	// Query id of method open
	m_szFunction = OLESTR("Open");
	m_hr = m_pDispDocs->GetIDsOfNames(IID_NULL, &m_szFunction,1,
									  LOCALE_USER_DEFAULT, &m_dispid_Open);

	// Prepare parameters for open method
	VARIANT		vArgsOpen[6];
	DISPPARAMS	dpOpen;
	dpOpen.cArgs		= 6;
	dpOpen.cNamedArgs   = 0;
	dpOpen.rgvarg		= vArgsOpen;

	VARIANT		vFalse, vTrue;
	vFalse.vt			= VT_BOOL;
	vFalse.boolVal		= FALSE;
	vTrue.vt			= VT_BOOL;
	vTrue.boolVal		= TRUE;


	m_bstrEmptyString = ::SysAllocString(OLESTR("")) ;

	vArgsOpen[5].vt			= VT_BSTR;
	vArgsOpen[5].bstrVal	= bstrOpenFile;
	vArgsOpen[4]			= vFalse;
	vArgsOpen[3]			= vTrue;
	vArgsOpen[2]			= vFalse;
	vArgsOpen[1].vt			= VT_BSTR;
	vArgsOpen[1].bstrVal	= m_bstrEmptyString;
	vArgsOpen[0].vt			= VT_BSTR;
	vArgsOpen[0].bstrVal	= m_bstrEmptyString;

	//Execute open method
	m_hr=m_pDispDocs->Invoke(m_dispid_Open,IID_NULL,LOCALE_USER_DEFAULT,
							 DISPATCH_METHOD,&dpOpen,NULL,NULL,NULL);

	//Query activedocument interface
	m_szFunction = OLESTR("ActiveDocument");
	m_hr = m_pDispApp->GetIDsOfNames(IID_NULL, &m_szFunction, 1,
								     LOCALE_USER_DEFAULT,&m_dispid_ActiveDoc);
	m_hr = m_pDispApp->Invoke(m_dispid_ActiveDoc,IID_NULL,
							  LOCALE_USER_DEFAULT, DISPATCH_PROPERTYGET,
							  &m_dpNoArgs,&m_vResult,NULL,NULL);
	m_pDispActiveDoc = m_vResult.pdispVal;

	//Prepare arguments for save as .txt
	VARIANT			vArgsSaveAs[11];
	DISPPARAMS		dpSaveAs;
	dpSaveAs.cArgs			=   11;
	dpSaveAs.cNamedArgs		=   0;
	dpSaveAs.rgvarg			=   vArgsSaveAs;

	vArgsSaveAs[10].vt		=   VT_BSTR;
	vArgsSaveAs[10].bstrVal =	bstrSaveFile;		//Filename
	vArgsSaveAs[9].vt		=   VT_I4;
	vArgsSaveAs[9].lVal		=   2;                  //FileFormat(wdFormatText = 2)
	vArgsSaveAs[8]			=   vFalse;				//LockComments
	vArgsSaveAs[7].vt		=   VT_BSTR;
	vArgsSaveAs[7].bstrVal  =   m_bstrEmptyString;  //Password
	vArgsSaveAs[6].vt		=   VT_BOOL;
	vArgsSaveAs[6].boolVal  =   TRUE;               //AddToRecentFiles
	vArgsSaveAs[5].vt		=   VT_BSTR;
	vArgsSaveAs[5].bstrVal  =   m_bstrEmptyString;  //WritePassword
	vArgsSaveAs[4]			=   vFalse;             //ReadOnlyRecommended
	vArgsSaveAs[3]			=   vFalse;             //EmbedTrueTypeFonts
	vArgsSaveAs[2]			=   vFalse;             //SaveNativePictureFormat
	vArgsSaveAs[1]			=   vFalse;             //SaveFormsData
	vArgsSaveAs[0]			=   vFalse;				//SaveAsOCELetter

	// Query and execute SaveAs method
	m_szFunction = OLESTR("SaveAs");
	m_hr = m_pDispActiveDoc->GetIDsOfNames(IID_NULL,&m_szFunction,1,
										   LOCALE_USER_DEFAULT,&m_dispid_SaveAs);
	m_hr = m_pDispActiveDoc->Invoke(m_dispid_SaveAs, IID_NULL,
									LOCALE_USER_DEFAULT,DISPATCH_METHOD,
									&dpSaveAs,NULL,NULL,NULL);
	// Invoke the Quit method
    m_szFunction = OLESTR("Quit");
    m_hr = m_pDispApp->GetIDsOfNames(IID_NULL, &m_szFunction, 1,
									 LOCALE_USER_DEFAULT, &m_dispid_Quit);
    m_hr = m_pDispApp->Invoke(m_dispid_Quit, IID_NULL, LOCALE_USER_DEFAULT,
							  DISPATCH_METHOD, &m_dpNoArgs, NULL, NULL, NULL);

    //Clean-up
	::SysFreeString(bstrOpenFile) ;
	::SysFreeString(bstrSaveFile) ;
	::SysFreeString(m_bstrEmptyString) ;

    m_pDispActiveDoc->Release();
    m_pDispDocs->Release();
    m_pDispApp->Release();
    m_pUnk->Release();

    ::CoUninitialize();
}
int main(int argc, char* argv[])
{
	BSTR str1,str2 ;
	str1 = ::SysAllocString(OLESTR("C://doc1.doc"));
	str2 = ::SysAllocString(OLESTR("C://doc1.txt"));
	DocToTxt(str1,str2);
	return 0;
}
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  函数已经经过测试，使用前先判断word是否安装
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