WM_COMMAND message

Sent when the user selects a command item from a menu, when a control sends a notification message to its parent window, or when an accelerator keystroke is translated.

#define WM_COMMAND                      0x0111

Parameters

wParam

For a description of this parameter, see Remarks.

lParam

For a description of this parameter, see Remarks.

Return value

If an application processes this message, it should return zero.

Remarks

Use of the wParam and lParam parameters are summarized here.

Message Source wParam (high word) wParam (low word) lParam
Menu 0 Menu identifier (IDM_*) 0
Accelerator 1 Accelerator identifier (IDM_*) 0
Control Control-defined notification code Control identifier Handle to the control window

If an application enables a menu separator, the system sends a WM_COMMAND message with the low-word of the wParam parameter set to zero when the user selects the separator.

If a menu is defined with a MENUINFO.dwStyle value of MNS_NOTIFYBYPOS, WM_MENUCOMMAND is sent instead of WM_COMMAND.

Accelerators

Accelerator keystrokes that select items from the window menu are translated into WM_SYSCOMMAND messages.

If an accelerator keystroke occurs that corresponds to a menu item when the window that owns the menu is minimized, no WM_COMMAND message is sent. However, if an accelerator keystroke occurs that does not match any of the items in the window's menu or in the window menu, a WM_COMMAND message is sent, even if the window is minimized.

Requirements

Minimum supported client
Windows 2000 Professional [desktop apps only]
Minimum supported server
Windows 2000 Server [desktop apps only]
Header
Winuser.h (include Windows.h)

See also

Reference

HIWORD

LOWORD

Conceptual

Menus