RichEdit1.Lines.SaveToFile('aaa.RTF');     //保存为RTF格式
    RichEdit1.Lines.LoadFromFile('aaa.RTF');   //从RTF读取

var
  Stream: TStringStream;
begin
  Stream := TStringStream.Create;
  try
    RichEdit1.Lines.SaveToStream(Stream);
    // 获取RTF原始文本    //    ShowMessage(Stream.DataString);
   memo1.Text:= Stream.DataString;
  finally
    Stream.Free;
  end;
end;

procedure TForm3.FormCreate(Sender: TObject);
begin
    Memo1.Lines.LoadFromFile('aaa.RTF');
end;

procedure TForm3.RichEdit1Change(Sender: TObject);
begin
    RichEdit1.Lines.SaveToFile('aaa.RTF');     //保存为RTF格式
      Memo1.Lines.LoadFromFile('aaa.RTF');
end;