Delphi集合增删的另一种操作

D7

 1 unit Unit1;
 2
 3 interface
 4
 5 uses
 6   Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
 7   Dialogs, StdCtrls;
 8
 9 type
10   TForm1 = class(TForm)
11     Button1: TButton;
12     Button2: TButton;
13     Button3: TButton;
14     procedure Button1Click(Sender: TObject);
15     procedure Button2Click(Sender: TObject);
16     procedure Button3Click(Sender: TObject);
17   private
18     { Private declarations }
19   public
20     { Public declarations }
21   end;
22   TMyset001=set of (ss,aa,mm,tt);
23 var
24   Form1: TForm1;
25   Set01:TMyset001;
26 implementation
27
28 {$R *.dfm}
29
30 procedure TForm1.Button1Click(Sender: TObject);
31 begin
32   Include(Set01,aa);
33 end;
34
35 procedure TForm1.Button2Click(Sender: TObject);
36 begin
37   Include(Set01,ss);
38
39 end;
40
41 procedure TForm1.Button3Click(Sender: TObject);
42 begin
43   Exclude(Set01,ss);
44   Exclude(Set01,aa);
45   Exclude(Set01,ss);
46   if Set01=[] then
47   begin
48     //
49   end;
50 end;
51
52 end.