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4/8/2010

This message is posted when the user releases the middle mouse button while the cursor is located within the client area of a window. If another window has not captured the mouse, the OS posts the message to the window beneath the cursor. If another window has captured the mouse, the OS posts the message to the window that has captured the mouse.

A window receives this message through the WindowProcfunction for the window.

Syntax 

WM_MBUTTONUP 

fwKeys = 
wParam; 

xPos = LOWORD(
lParam); 

yPos = HIWORD(
lParam);

Parameters

fwKeys

Indicates the mouse buttons and keys that the user pressed. The following table shows the possible values, which can be combined.

Value Description

MK_CONTROL

The user pressed the CTRL key.

MK_LBUTTON

The user pressed the left mouse button.

MK_MBUTTON

The user pressed the middle mouse button.

MK_RBUTTON

The user pressed the right mouse button.

MK_SHIFT

The user pressed the SHIFT key.
xPos

Value of the low-order word of lParam. Specifies the x-coordinate of the pointer, 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 pointer, relative to the upper-left corner of the client area.

Return Value

An application that processes this message should return zero.

Requirements

Header windows.h
Library coredll.lib
Windows Embedded CE Windows CE .NET 4.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also