delphi 的内存复制处理

type
  TRecord=record
    a:DWord;
    b:array [0..99] of Char;
  end;
procedure TForm1.btn1Click(Sender: TObject);
var
  buff:array [0..SizeOf(TRecord)-1] of Byte;
  a :^TRecord;
begin
  a:=AllocMem(SizeOf(TRecord));
  buff[4]:=Ord('a');
  Move(buff,a^,10);
  ShowMessage(a^.b);
end;