inheritance - Delphi how to implement baseclass event? -

i have abstract delphi xe form acts base class family of forms used in application. trying figure out best way make function (on f1 keypress) opens wiki-page active form.

i'd function implemented @ base-class level , call when user presses f1 need advice on how in smart way. put keydown-event on base form gets overwritten if subform receives own keydown, @ point have manually call basekeydown. obviously, not optimal.. there way ensure catch f1 keypress @ baseclass level, random overloads nonwithstanding?

i running delphi xe on windows 7

you should override keydown method in base form class.

type   tbaseform = class(tform)   protected     procedure keydown(var key: word; shift: tshiftstate); override;   end;  procedure tbaseform.keydown(var key: word; shift: tshiftstate); begin   // processing here   // ...   inherited; // call inherited method call onkeydown if assigned end; 

this default implementation of kewdown method calls onkeydown events

procedure twincontrol.keydown(var key: word; shift: tshiftstate); begin   if assigned(fonkeydown) fonkeydown(self, key, shift); end;