WINEVENTPROC function pointer

Used to declare a pointer to an application-defined callback function that the system calls in response to events that are generated by an accessible object.

Syntax

typedef void ( CALLBACK *WINEVENTPROC)(
   HWINEVENTHOOK hWinEventHook,
   DWORD         event,
   HWND          hwnd,
   LONG          idObject,
   LONG          idChild,
   DWORD         dwEventThread,
   DWORD         dwmsEventTime
);

Parameters

• hWinEventHook
  Handle to an event hook instance. This value is returned by SetWinEventHook when the hook function is installed, and it is specific to each instance of the hook function.

• event
  Specifies the event that occurred. This value is one of the event constants.

• hwnd
  Handle to the window that generates the event, or NULL if no window is associated with the event; for example, the mouse pointer is not associated with a window.

• idObject
  Identifies the object that is associated with the event. This is either one of the object identifiers or a custom object ID.

• idChild
  Identifies whether the event was triggered by an object or a child element of the object. If this value is CHILDID_SELF, the event was triggered by the object; if this value is a child ID, the event was triggered by a child element.

• dwEventThread
  Identifies the thread that generated the event, or the thread that owns the current window.

• dwmsEventTime
  Specifies the time, in milliseconds, that the event was generated.

Return value

This function pointer does not return a value.

Remarks

For more information, see WinEventProc.

Requirements

Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows Server 2003 [desktop apps only]
Redistributable	Active Accessibility 1.3 RDK on Windows NT 4.0 with SP6 and later and Windows 95
Header	Winuser.h (WINVER >= 0x0500) (include Windows.h)