ACDUAL: Adds Dual Interfaces to an Automation Application

Click to open or copy the ACDUAL project files.

ACDUAL demonstrates how to add dual-interface support to an MFC-based Automation (formerly OLE Automation) application with the native compiler COM support. See the MFC ACDUAL sample for more information.

The differences between this sample and the MFC sample with the same name are:

1. The COleDispatchDriver class is no longer necessary. Instead, #import is used to import a type library.
   
   
2. The _bstr_t and _variant_t wrapper classes are used to simplify operations of BSTR and VARIANT types.
   
   
3. The __declspec(property) is used to simplify assignment operations for properties of COM objects.
   
   
4. COM error handling is now performed by using the _com_error class.

With the Visual C++ native compiler COM support, the resulting sample code is shorter and more efficient. The MFC-based ACDUAL sample uses both dual interfaces and dispinterfaces only. Compare this sample with the MFC version to see the differences in source code.

This sample demonstrates the following keywords:

dispinterface; #import; _com_ptr_t; _variant_t; _bstr_t; _com_error.

See also Compiler COM Support, MFC ACDUAL sample.