Format to access a class function pointer which is a member of a struct

[Pranav Singhania]

Below is my struct declaration where

ticket_booking

is my class.

struct MENUITEM {
      enum ITEMTYPE type;
      char *name;
      char *helpstring;
      void (ticket_booking :: *p)();
      void *s;
};

And now below I want to access the class function pointer which doesn't seem to be happening

      case CR:
            {		
		 struct MENUITEM *itemp = mp->menuitemlist[mp->curritem];
                  if(itemp->type == MI_PARENT)
                  {
			struct MENU *mp2 = (struct MENU*) itemp->(ticket_booking :: *p) (); //ERROR 1
                        displaymenu(mp);
                        mp = mp2;
                  }
                  else if(itemp->type == MI_ACTION)
                  {

			fp = (void(*) ()) itemp->(ticket_booking :: *p) (); //ERROR 2
                    fp();
                  }
            }
			break;

I tried all possible ways but none seem to work and this is causing the whole project to go flat. Immediate suggestion would help, not very familiar with class function pointers.

[vince1027]

Read this: http://www.parashift.com/c++-faq/pointers-to-members.html

In general, don't keep a reference to member functions; keep a reference to the instance instead. You cannot invoke a member function without the instance it needs to invoke on (because the this context would be meaningless). Keeping a reference to the instance not only makes this easier but also make your code readable and easier to understand for others.