兩個判斷式, 那個是對的? 都錯. 那TypeOf是怎麼使用的呢?

procedure TForm1.Button1Click(Sender: TObject);
var
  a:TButton;
  b:TBitbtn;
begin
  a:=TTestObj.Create;
  b:=TSecond.Create;
//  if TypeOf(TButton)=TypeOf(TBitbtn) then
  if TypeOf(a)=TypeOf(b) then
    showmessage('yes')
  else
    showmessage('no');
  a.Free;
  b.Free;
end;

What version of Delphi are you using? It can't get compiled under Delphi 7. Anyway, as far as I remember, TypeOf is a function used in the good DOS days (i.e. Borland/Turbo Pascal). In Delphi, I think using the is operator is better.