WM_MENUSELECT
uItem = (UINT) LOWORD(wParam); /* item identifier */
fuFlags = (UINT) HIWORD(wParam); /* menu-item flags */
hmenu = (HMENU) lParam; /* pop-up menu handle */
The WM_MENUSELECT message is sent to a menu's owner window when the user selects a menu item.
uItem
Value of the low-order word of wParam. If the selected item is a command item, this parameter contains the identifier of the menu-item. If the selected item invokes a pop-up menu, this parameter is undefined, but the hmenu parameter specifies the handle of the pop-up menu.
fuFlags
Value of the high-order word of wParam. Specifies one or more menu flags. This parameter can be a combination of the following values:
| Flag | Description |
| MF_BITMAP | Item displays a bitmap. |
| MF_CHECKED | Item is checked. |
| MF_DISABLED | Item is disabled. |
| MF_GRAYED | Item is grayed. |
| MF_MOUSESELECT | Item was selected with the mouse. |
| MF_OWNERDRAW | Item is an owner-draw item. |
| MF_POPUP | Item invokes a pop-up menu. |
| MF_SYSMENU | Item is contained in the System menu. The hmenu parameter identifies the System menu associated with the message. |
hmenu
Value of lParam. Identifies the pop-up menu invoked by the selected menu item.
An application should return zero if it processes this message.
If the low-order word of the lParam parameter contains -1 and the high-order word of the lParam parameter contains 0, Windows has closed the menu because the user pressed ESC or clicked outside the menu.