动态创建Tabsheet遇到困难

procedure TForm1.pgc1Change(Sender: TObject);
var
  I: Integer;
  Richedit: TRichedit;
begin
  if (pgc1.ActivePageIndex >= 0) and (pgc1.ActivePageIndex <= pgc1.PageCount -1) then
  begin
    with pgc1.Pages[pgc1.ActivePageIndex] do
      for I := 0 to ControlCount - 1 do
      begin
        if Controls[I] is TRichedit then
          Richedit := Controls[I];
      end;
 
    if Richedit <> nil then
    begin
      // 修改属性
      Richedit.....
    end;
  end;
end;