CONVERTIR UN BSTR EN CHAR* ET UN CHAR* EN BSTR

////////////////////////////////
void BSTRtoASC (BSTR str, char * &strRet) {

    if ( str != NULL ) {
        unsigned long length = WideCharToMultiByte ( 
			CP_ACP,			
                                                0,							str,				
			SysStringLen(str),  				                                NULL,							0,				
                                                NULL,							NULL				
		                ); 
		
        strRet = new char[length];

        length = WideCharToMultiByte ( 
			CP_ACP,			
                                                0,							str,				
			SysStringLen(str),  				                                reinterpret_cast <char *>(strRet),					length,				
                                                NULL,							NULL				
		                ); 

        strRet[length] = '\0';
    }

}

	
////////////////////////////////
void ASCtoBSTR (char * str, BSTR * strRet) {
	
    if ( str != NULL ) {
        unsigned long length = strlen(str);
		
        int ResultLength = MultiByteToWideChar (
		    CP_ACP,
                                    MB_PRECOMPOSED,				
                                    reinterpret_cast <char *>(str),   
	                    length,	
                                    NULL,				
	                    0							); 

        *strRet = SysAllocStringLen( NULL, ResultLength);
        
        MultiByteToWideChar (
		    CP_ACP,
                                    MB_PRECOMPOSED,				
                                    reinterpret_cast <char *>(str),   
	                    length,	
                                    *strRet,				
	                    ResultLength							); 
    }

}