Delphi中MDI的问题

Question

procedure TfrmMain.showform(FormClass: TFormClass);
var
  i: integer;
begin
  for i := 0 to self.MDIChildCount - 1 do
    if (MDIChildren[i] is FormClass) then
    begin
      self.MDIChildren[i].BringToFront;
     // sendmessage(MDIChildren[i].handle,wm_syscommand,SC_RESTORE,0);
      MDIChildren[i].SetFocus;
      Exit;
    end;
  FormClass.Create(self);
end;调用时：
showform(Tform1);

Answer 1

Delphi本身有个函数Assigned能用在MDI中吗，试过好像不行。但是在非MDI中好像可行。