MOUSEHOOKSTRUCTEX structure (Windows)

Applies to: desktop apps only

Contains information about a mouse event passed to a WH_MOUSE hook procedure, MouseProc.

This is an extension of the MOUSEHOOKSTRUCT structure that includes information about wheel movement or the use of the X button.

Syntax

typedef struct tagMOUSEHOOKSTRUCTEX {
  MOUSEHOOKSTRUCT MOUSEHOOKSTRUCT;
  DWORD           mouseData;
} MOUSEHOOKSTRUCTEX, *PMOUSEHOOKSTRUCTEX, *LPMOUSEHOOKSTRUCTEX;

Members

MOUSEHOOKSTRUCT

Type: MOUSEHOOKSTRUCT

The members of a MOUSEHOOKSTRUCT structure make up the first part of this structure.

mouseData

Type: DWORD

If the message is WM_MOUSEWHEEL, the HIWORD of this member is the wheel delta. The LOWORD is undefined and reserved. A positive value indicates that the wheel was rotated forward, away from the user; a negative value indicates that the wheel was rotated backward, toward the user. One wheel click is defined as WHEEL_DELTA, which is 120.

If the message is WM_XBUTTONDOWN, WM_XBUTTONUP, WM_XBUTTONDBLCLK, WM_NCXBUTTONDOWN, WM_NCXBUTTONUP, or WM_NCXBUTTONDBLCLK, the HIWORD of mouseData specifies which X button was pressed or released, and the LOWORD is undefined and reserved. This member can be one or more of the following values. Otherwise, mouseData is not used.

Value	Meaning
XBUTTON1 0x0001	The first X button was pressed or released.
XBUTTON2 0x0002	The second X button was pressed or released.

 

Requirements

See also

Reference

MouseProc

MOUSEHOOKSTRUCT

WM_MOUSEWHEEL

WM_XBUTTONDOWN

WM_XBUTTONUP

WM_XBUTTONDBLCLK

WM_NCXBUTTONDOWN

WM_NCXBUTTONUP

WM_NCXBUTTONDBLCLK

Conceptual

Hooks

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Build date: 2/3/2012