function GetAnsistringRefcount(const S: string): Cardinal;
asm
 or eax, eax
 jz @done
 sub eax, 8
 mov eax, dword ptr [eax]
 @done:
end;
procedure TForm1.Button1Click(Sender: TObject);
var
 S1, S2: string;
begin
 memo1.lines.Add(Format('Refcount at start: %d',
  [GetAnsistringRefcount(S1)]));
 S1 := StringOfChar('A', 10);
 memo1.lines.Add(Format('Refcount after assignment: %d',
  [GetAnsistringRefcount(S1)]));
 S2 := S1;
 memo1.lines.Add(Format('Refcount after S2:=S1: %d',
  [GetAnsistringRefcount(S1)]));
 S2 := S1 + S2;
 memo1.lines.Add(Format('Refcount after S2:=S1+S2: %d',
  [GetAnsistringRefcount(S1)]));
end;