WM_MBUTTONDBLCLK

2.x

WM_MBUTTONDBLCLK
fwKeys = wParam;          /* key flags                     */
xPos = LOWORD(lParam);    /* horizontal position of cursor */
yPos = HIWORD(lParam);    /* vertical position of cursor   */

The WM_MBUTTONDBLCLK message is sent when the user double-clicks the middle mouse button.

Parameters

fwKeys

Value of wParam. Indicates whether various virtual keys are down. This parameter can be any combination of the following values:

Value

Description

MK_CONTROL	Set if CTRL key is down.
MK_LBUTTON	Set if left button is down.
MK_MBUTTON	Set if middle button is down.
MK_RBUTTON	Set if right button is down.
MK_SHIFT	Set if SHIFT key is down.

xPos

Value of the low-order word of lParam. Specifies the x-coordinate of the cursor. The coordinate is relative to the upper-left corner of the window.

yPos

Value of the high-order word of lParam. Specifies the y-coordinate of the cursor. The coordinate is relative to the upper-left corner of the window.

Return Value

An application should return zero if it processes this message.

Comments

Only windows that have the CS_DBLCLKS class style can receive WM_MBUTTONDBLCLK messages. Windows generates a WM_MBUTTONDBLCLK message when the user presses, releases, and again presses the middle mouse button within the system's double-click time limit. Double-clicking the middle mouse button actually generates four messages: a WM_MBUTTONDOWN message, a WM_MBUTTONUP message, the WM_MBUTTONDBLCLK message, and another WM_MBUTTONUP message.