You can create new documents in the Visual C++ environment other than simple text files or file types that the build system recognizes. Because Visual C++ is an Active document container, you can create and work in document types such as those created by Microsoft Word or Microsoft Excel.
To create a new Active document within Visual C++
Note You should use the extension associated with the appropriate COM component, such as .xls for a Microsoft Excel spreadsheet. Whenever you open an Active document in the development environment, the extension is used to identify the associated Active component.
To open an existing document in a Visual C++ project
If the document is an Active document, it is opened within the development environment and the toolbars for the associated COM component become available.