Automation for Configuration and SelectedItem objects
You can automate the build and selected item processes in Visual Studio.
Automation for builds
Build or configuration has an automation model that is provided when you implement IVsCfgProvider. For more information, see Understand build configurations.
If you create a VSPackage and want to control configuration options, you must use the automation model.
Automation for SelectedItem
You do not have to provide an implementation for the SelectedItem object because Visual Studio contains a standard implementation. However, you can implement the SelectedItem object if you prefer. You must implement an object that contains the SelectedItem interface and return a response to a call to the GetPropertyPage method with VSITEMID set to __VSHPROPID.VSHPROPID_ExtSelectedItem.