1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:

procedure TMemoryField.Shuffle;
var
  i, i2             : Integer;

  procedure Swap(i1, i2: Integer);
  var
    Help            : Integer;
  begin
    Help := TCard(FCards.Items[i1]).Value;
    TCard(FCards.Items[i1]).Value := TCard(FCards.Items[i2]).Value;
    TCard(FCards.Items[i2]).Value := Help;
  end;

begin
  for i := 0 to FCards.Count - 1 do
  begin
    i2 := Random(FCards.Count - 1);
    Swap(i, i2);
  end;
end;