C / C++ / MFC

_bstr_t bstrText = L"text";
//You can let CString do the conversion from wchar to char:
CString strText = (LPCWSTR)bstrText;
//or let _bstr_t do it:
CString strText2 = (LPCSTR)bstrText;

_bstr_t ab = SOmethingDoneTo (a) 

char* pszText = "this is a text"; //This works
wchar_t* pszwText = L"so is this"; //This works also

char* pszText2 = L"doesn't work"; 
//This generates a compiler error - can't convert from wchar to char

wchar* pszwText2 = "doesn't work either"
//this also generates compiler error.

CString strText = _T("This is a text");
_bstr_t bstrText = (LPCTSTR)strText;
//Now _bstr_t will construct itself from a LPCTSTR - ususally a const char*

_bstr_t b_dataBaseName = SysAllocString (dataBaseName);

error C2664: 'SysAllocString' : cannot convert parameter 1 from 'char *' to 'const unsigned short *'

USES_CONVERSION;

_bstr_t b_databaseName = T2W( dataBaseName );

error C2664: 'MakeDB' : cannot convert parameter 1 from 'class _bstr_t' to 'unsigned short ** '

	  char* dataBaseName = new char[dataBaseName0.GetLength() +1];

	  strcpy(dataBaseName, dataBaseName0);
	
//	  BSTR b_dataBaseName = SysAllocString (dataBaseName);

	  USES_CONVERSION;
	  
	  _bstr_t b_dataBaseName = T2W( dataBaseName );
	   char* strFile = new char[strFile0.GetLength() +1];

	  strcpy(strFile, strFile0);

//	  _bstr_t b_strFile = SysAllocString (strFile);

	  _bstr_t b_strFile = T2W(strFile);

      _Class1Ptr ptr;
 
       ptr.CreateInstance(__uuidof(Class1));

        ptr->MakeDB( b_strFile, b_dataBaseName);

//	      ptr->MakeDB( LPCTSTR(strFile), LPCTSTR(dataBaseName));

//		SysFreeString (b_dataBaseName);

//		SysFreeString (b_strFile);

                delete[] etc

USES_CONVERSION;

LPCWSTR pszwDatabaseName = T2W( (LPCTSTR)dataBaseName0 );
LPCWSTR pszwFileName = T2W( (LPCTSTR)strFile0 );

_Class1Ptr ptr;        
ptr.CreateInstance(__uuidof(Class1));
ptr->MakeDB( pszwFileName, pszwDatabaseName );

error C2664: 'MakeDB' : cannot convert parameter 1 from 'const unsigned short *' to 'unsigned short **

Public Function MakeDB(txtPMAFilename As String, dataBaseName As String)

HWND hWndExcel = ::FindWindow( _T("XLMAIN"), NULL );

HWND hWndExcel = ::FindWindow( _T("XLMAIN"), _T("Microsoft Excel - secrets.xls") );

OSVERSIONINFO os;
::GetVersionEx(&os);

if ( os.dwMajorVersion>=5 )
   SetLayeredWindowAttributes(...).