mainunit.pas

《Delphi 7经典问题解析》源代码 第一到七章 基础篇源程序 应用篇源程序

unit mainunit;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls,Registry;

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Button1: TButton;
    Button2: TButton;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    procedure CanUseTaskMgr(Value:Boolean);
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.CanUseTaskMgr(Value:Boolean);
var
 Reg:TRegistry;
begin
 Reg:=TRegistry.Create;
 try
  Reg.RootKey:=HKEY_CURRENT_USER;
  if Reg.OpenKey('\Software\Microsoft\Windows\CurrentVersion\Policies\System', True) then
     begin
      Reg.WriteBool('DisableTaskMgr',Value);
     end;
  finally
   Reg.CloseKey;
   Reg.Free;
  end;
end;

procedure TForm1.FormCreate(Sender: TObject);
var
 Reg:TRegistry;
begin
 Reg:=TRegistry.Create;
 try
  Reg.RootKey:=HKEY_CURRENT_USER;
  if Reg.KeyExists('\Software\Microsoft\Windows\CurrentVersion\Policies\System') then
   begin
    Reg.OpenKey('\Software\Microsoft\Windows\CurrentVersion\Policies\System',False);
    if Reg.ValueExists('DisableTaskMgr') then
     begin
      if (Reg.ReadBool('DisableTaskMgr')) then
       begin
        Label2.Caption:='否';
        Button1.Enabled:=False;
        Button2.Enabled:=True;
       end
       else
       begin
        Label2.Caption:='是';
        Button1.Enabled:=True;
        Button2.Enabled:=False;
       end;
     end
     else
     begin
      Label2.Caption:='是';
      Button1.Enabled:=True;
      Button2.Enabled:=False;
     end;
   end
   else
   begin
    Label2.Caption:='是';
    Button1.Enabled:=True;
    Button2.Enabled:=False;
   end;
 finally
  Reg.CloseKey;
  Reg.Free;
 end; 
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
 CanUseTaskMgr(True);
 Label2.Caption:='否';
 Button1.Enabled:=False;
 Button2.Enabled:=True;
 ShowMessage('任务管理器已经被禁止使用!');
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
 CanUseTaskMgr(False);
 Label2.Caption:='是';
 Button1.Enabled:=True;
 Button2.Enabled:=False;
 ShowMessage('任务管理器已经被允许使用!');
end;

end.