IShellIcon 

The IShellIcon interface is used to obtain an icon index for an IShellFolder113Z9WE object. Only one instance of the interface for the folder  is required instead of an instance for each object, as is the case for IExtractIcon.

When to Implement

Implement IShellIcon as part of an IShellFolder113Z9WE implementation as a quick way to obtain the icon for an object in the folder.

If IShellIcon is not implemented by an IShellFolder object, IShellFolder::GetUIObjectOf(..., IID_IExtractIcon, ...) is used to get an icon for all objects.

When to Use

Use IShellIcon when getting icon indexes for items in a shell folder.

Methods in Vtable Order