Enables developers to provide a custom, managed implementation of the IUnknown::QueryInterface(REFIID riid, void **ppvObject) method.
Assembly: mscorlib (in mscorlib.dll)
Returns an interface according to a specified interface ID.
This class permits advanced users to provide a customized managed implementation of the QueryInterface method.
Managed and native applications can use the customized implementation to return a specific interface for a specified interface ID, except for IID_IUnknown. That is, when QueryInterface is called, it will ignore custom implementations if its riid parameter is set to IID_IUnknown. However, you may still return IUnknown as the ppvObject.
Developers can provide custom implementations for all interfaces (except for IUnknown) if they define and implement a valid corresponding interface.
Available since 4.5
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Windows Phone Silverlight
Available since 8.0
Available since 8.1