WM_MBUTTONDOWN

2.x

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

The WM_MBUTTONDOWN message is sent when the user presses 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_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.

See Also

WM_MBUTTONDBLCLK, WM_MBUTTONUP