delphi TMemoryStream 和TStringStream 转换

procedure TFormTestRichText.btn1Click(Sender: TObject);
begin
  //cxrchdt1.Lines.SaveToFile('d:	est.txt');
  mStream := TMemoryStream.Create;
  cxrchdt1.Lines.SaveToStream(mStream);
  ShowMessage(IntToStr(mStream.Size));
end;

procedure TFormTestRichText.btn2Click(Sender: TObject);
var
  c: Char;
  s1, s2: string;
  vMemoryStream: TMemoryStream;
begin
 //cxrchdt1.Lines.LoadFromFile('d:	est.txt');
  cxrchdt1.Lines.LoadFromStream(mStream);

  s1 := '';
  mStream.Position := 0;                       {指针到开始}
  while mStream.Position < mStream.Size do          {循环读出}
  begin
    mStream.Read(c, 1);                         {每读出一个字节, 指针会自动移到新的位置}
    s1 := s1 + c + '';                   {用文本记录}
   // s2 := s2 + IntToHex(Byte(c),2) + ' '; {用两位数的十六进制记录}
  end;

  vMemoryStream := TStringStream.create(s1);
  cxrchdt1.Lines.LoadFromStream(vMemoryStream);
end;