用一个 Byte 值保存八种状态的实例:

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准备工作:
1、在空白窗体上添加 CheckListBox1;
2、添加四个 Button, 并激活 Button1 的 OnClick 事件;
3、激活窗体的 OnCreate 事件.

 

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unit Unit1;



interface



uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls, CheckLst;



type

  TForm1 = class(TForm)

    CheckListBox1: TCheckListBox;

    Button1: TButton;

    Button2: TButton;

    Button3: TButton;

    Button4: TButton;

    procedure FormCreate(Sender: TObject);

    procedure Button1Click(Sender: TObject);

  private

    { Private declarations }

  public

    { Public declarations }

  end;



var

  Form1: TForm1;



implementation

var

  b: Byte;



{$R *.dfm}



procedure TForm1.FormCreate(Sender: TObject);

begin

  CheckListBox1.Items.CommaText := 'A,B,C,D,E,F,G,H';

  Button1.Caption := '±£´æ״̬';

  Button2.Caption := '»Ö¸´×´Ì¬';

  Button3.Caption := 'È«Ñ¡';

  Button4.Caption := 'È«²»Ñ¡';

  Button1.Tag := 1;

  Button2.Tag := 2;

  Button3.Tag := 3;

  Button4.Tag := 4;

  Button2.OnClick := Button1.OnClick;

  Button3.OnClick := Button1.OnClick;

  Button4.OnClick := Button1.OnClick;



end;



procedure TForm1.Button1Click(Sender: TObject);

var

  i: Integer;

begin

  if TButton(Sender).Tag = 1 then b := 0;

  for i := 0 to CheckListBox1.Count - 1 do

    case TButton(Sender).Tag of

      1: if CheckListBox1.Checked[i] then b := b or (1 shl i);

      2: CheckListBox1.Checked[i] := Odd(b shr i);

      3: CheckListBox1.Checked[i] := True;

      4: CheckListBox1.Checked[i] := False;

    end;



end;

end.

{

--------------------------------------------------------------------------------

用集合的方式重新做前一次的例子(窗体设计与测试效果同前):

--------------------------------------------------------------------------------

}



unit Unit1;



interface



uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls, CheckLst;



type

  TForm1 = class(TForm)

    CheckListBox1: TCheckListBox;

    Button1: TButton;

    Button2: TButton;

    Button3: TButton;

    Button4: TButton;

    procedure FormCreate(Sender: TObject);

    procedure Button1Click(Sender: TObject);

  private

    { Private declarations }

  public

    { Public declarations }

  end;



var

  Form1: TForm1;



implementation

var

  set1: set of 0..7; {准备用自定义的集合变量 set1 储存下面的 8 种状态}





{$R *.dfm}



procedure TForm1.FormCreate(Sender: TObject);

begin

  CheckListBox1.Items.CommaText := 'A,B,C,D,E,F,G,H';

  Button1.Caption := '保存状态';

  Button2.Caption := '恢复状态';

  Button3.Caption := '全选';   

  Button4.Caption := '全不选';
  Button1.Tag := 1;

  Button2.Tag := 2;

  Button3.Tag := 3;

  Button4.Tag := 4;

  Button2.OnClick := Button1.OnClick;

  Button3.OnClick := Button1.OnClick;

  Button4.OnClick := Button1.OnClick;



end;



procedure TForm1.Button1Click(Sender: TObject);

var

  i: Integer;

begin

  if TButton(Sender).Tag = 1 then set1 := [];

  for i := 0 to CheckListBox1.Count - 1 do

    case TButton(Sender).Tag of

      1: if CheckListBox1.Checked[i] then Include(set1, i);

      2: CheckListBox1.Checked[i] := i in set1;

      3: CheckListBox1.Checked[i] := True;

      4: CheckListBox1.Checked[i] := False;

    end;

end;

end.