The CheckMenuItem function sets the state of the specified menu item's check-mark attribute to either selected or clear.
Note The CheckMenuItem function has been superseded by the SetMenuItemInfo function. You can still use CheckMenuItem, however, if you do not need any of the extended features of SetMenuItemInfo.
DWORD CheckMenuItem(
HMENU hmenu, // handle to menu
UINT uIDCheckItem, // menu item to check or uncheck
UINT uCheck // menu item options //这个是关键的参数，如果要修改，就从这里吧
);
Parameters
hmenu
[in] Handle to the menu of interest.
uIDCheckItem
[in] Specifies the menu item whose check-mark attribute is to be set, as determined by the uCheck parameter.
uCheck
[in] Specifies flags that control the interpretation of the uIDCheckItem parameter and the state of the menu item's check-mark attribute. This parameter can be a combination of either MF_BYCOMMAND, or MF_BYPOSITION and MF_CHECKED or MF_UNCHECKED. Value Meaning
MF_BYCOMMAND Indicates that the uIDCheckItem parameter gives the identifier of the menu item. The MF_BYCOMMAND flag is the default, if neither the MF_BYCOMMAND nor MF_BYPOSITION flag is specified.
MF_BYPOSITION Indicates that the uIDCheckItem parameter gives the zero-based relative position of the menu item.
MF_CHECKED Sets the check-mark attribute to the selected state.
MF_UNCHECKED Sets the check-mark attribute to the clear state.
对这个函数
TO change parameter uCheck into MF_UNCHECKED or MF_CHECKED， this is the routin to destination.
