ICatInformation

The ICatInformation interface provides methods for obtaining information about the categories implemented or required by a certain class, as well as information about the categories registered on a given machine.

When to Implement

There is no need to implement this interface. The Component Category Manager, a system-provided COM object that can be instantiated by using CoCreateInstance, implements ICatInformation.

When to Use

Call the methods of ICatInformation to obtain a listing of available categories, enumerate classes that belong to a particular category, and determine if a class belongs to a specific category.

Information on using component categories can be found in Component Categories Manager Implementation.

Methods in Vtable Order

IUnknown Methods

Description

QueryInterface

Returns pointers to supported interfaces.

AddRef

Increments reference count.

Release

Decrements reference count.

ICatInformation Methods

Description

EnumCategories

Returns an enumerator for the component categories registered on the system.

GetCategoryDesc

Retrieves the localized description string for a specific category ID.

EnumClassesOfCategories

Returns an enumerator over the classes that implement/require a certain set of categories.

IsClassOfCategories

Determines if a class implements/requires the specified categories.

EnumImplCategoriesOfClass

Returns an enumerator over the CATIDs implemented by the specified class.

EnumReqCategoriesOfClass

Returns an enumerator over the CATIDs required by the specified class.

See Also

ICatRegister