At first,I have to confess that I made a misunderstanding on the "EnableMenuItem",this function is to enable the "Menu Item" while I assume it also can enable the "Menu"(Please notice that what is "Menu Item" and "Menu"). Actually there is another function
which is used to enable "Menu"--"ModifyMenu". The fixed-mindset is horrible.
Attaching the using for these functions.
1) EnableMenuItem(GetMenu(),1, MF_BYPOSITION | MF_DISABLED | MF_GRAYED );
2) ModifyMenu(GetMenu(), 2, MF_BYPOSITION | MF_GRAYED ,0,"&Add ");
3) InsertMenu
4) RemoveMenu