title	Event handling
description	Learn how Microsoft C++ extensions support both COM and native event handling.
ms.date	11/20/2020
helpviewer_keywords	event handling [C++]

Event handling

Event handling is primarily supported for COM classes (C++ classes that implement COM objects, typically using ATL classes or the coclass attribute). For more information, see Event handling in COM.

Event handling is also supported for native C++ classes (C++ classes that don't implement COM objects). Native C++ event handling support is deprecated and will be removed in a future release. For more information, see Event handling in native C++.

Note

Event attributes in native C++ are incompatible with Standard C++. They don't compile when you specify /permissive- conformance mode.

Event handling supports both single- and multithreaded usage. It protects data from simultaneous multithread access. You can derive subclasses from event source or receiver classes. These subclasses support extended event sourcing and receiving.

The Microsoft C++ compiler includes attributes and keywords for declaring events and event handlers. The event attributes and keywords can be used in CLR programs and in native C++ programs.

Article	Description
event_source	Creates an event source.
event_receiver	Creates an event receiver (sink).
__event	Declares an event.
__raise	Emphasizes the call site of an event.
__hook	Associates a handler method with an event.
__unhook	Disassociates a handler method from an event.

See also

C++ language reference
Keywords