WM_MBUTTONDBLCLK
The
WM_MBUTTONDBLCLK message is posted when the user double-clicks the middle mouse
button while the cursor is in the client area of a window. If the mouse is not
captured, the message is posted to the window beneath the cursor. Otherwise,
the message is posted to the window that has captured the mouse.
WM_MBUTTONDBLCLK
fwKeys = wParam; // key flags
xPos = LOWORD(lParam); // horizontal position of cursor
yPos = HIWORD(lParam); // vertical position of cursor
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 the CTRL key is
down. |
|
MK_LBUTTON |
Set if the
left mouse button is down. |
|
MK_MBUTTON |
Set if the
middle mouse button is down. |
|
MK_RBUTTON |
Set if the
right mouse button is down. |
|
MK_SHIFT |
Set if the 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 client area.
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 client area.
Return Values
If an
application processes this message, it should return zero.
Remarks
Only windows
that have the CS_DBLCLKS style can receive WM_MBUTTONDBLCLK messages, which
Windows generates whenever 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:
WM_MBUTTONDOWN, WM_MBUTTONUP, WM_MBUTTONDBLCLK, and WM_MBUTTONUP again.
An
application can use the MAKEPOINTS macro to convert the lParam
parameter to a POINTS structure.
See Also