系统闲置自动退出【Delphi】

为了安全起见，ERP系統常常需要在闲置(用戶沒有键盘和鼠标的操作)一段时间后，自动退出，以防止他人冒名操作。软件在设计时，代码要分几段进行：取得系统闲置时长，用定时器每过一段时间检查一次闲置时长是否达到系统设置的时长，如果达到，就退出系统。下面是 Delphi的实例原码。

閑置时间Delphi的函数

function Tform1.LastInput:Dword;
var
 Linput:TLastInputInfo;
begin
 result:=0;
 try
  Linput.cbSize:=SizeOf(TLastInputInfo);
  GetLastInputInfo(Linput);
  Result:=((GetTickCount - Linput.dwTime) div 1000 );
 except
 end;
end;

界面判断与退出完整代码。

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ExtCtrls, AppEvnts, StdCtrls, Spin;

type
  TForm1 = class(TForm)
    ApplicationEvents1: TApplicationEvents;
    Timer1: TTimer;
    Edit1: TEdit;
    SpinEdit1: TSpinEdit;
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    procedure ApplicationEvents1Idle(Sender: TObject; var Done: Boolean);
    procedure ApplicationEvents1Message(var Msg: tagMSG;
      var Handled: Boolean);
    procedure Timer1Timer(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
    Mouse : TPoint;
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  IdleStart : TDateTime;

implementation

{$R *.dfm}

procedure TForm1.ApplicationEvents1Idle(Sender: TObject;
  var Done: Boolean);
begin
  IF NOT Timer1.Enabled THEN
    BEGIN
      Timer1.Enabled := True;
      IdleStart := Now;
    END;
  Done := True;
end;

procedure TForm1.ApplicationEvents1Message(var Msg: tagMSG;
  var Handled: Boolean);
Var
  I : SmallInt;
begin
  IF Msg.message = WM_MOUSEWHEEL then
    BEGIN
      Msg.message := WM_KEYDOWN;
      Msg.lParam := 0;
      I := HiWord(Msg.wParam);
      IF I > 0 THEN
          Msg.wParam := VK_UP
      ELSE
          Msg.wParam := VK_DOWN;
      Handled := False;
    END
  ELSE IF (Msg.Message = WM_MOUSEMOVE) THEN
    BEGIN
      IF (Timer1.Enabled) AND (Self.Active) THEN
      BEGIN
        IF (Abs(Msg.pt.X-Mouse.X) > 2) AND (Abs(Msg.pt.Y - Mouse.Y) > 2) THEN
        BEGIN
          Mouse.X := Msg.pt.X;
          Mouse.Y := Msg.pt.Y;
          Timer1.Enabled := False;
          Edit1.Text := '0';
        END;
      END;
    END
  ELSE IF ((Msg.Message = WM_LBUTTONDOWN) OR (Msg.Message = WM_MBUTTONDOWN) OR (Msg.Message = WM_RBUTTONDOWN) OR (Msg.Message = WM_KEYDOWN)) THEN
    BEGIN
      Timer1.Enabled := False;
      Edit1.Text := '0';
    END;
end;

procedure TForm1.Timer1Timer(Sender: TObject);
begin
  IF Round((Now - IdleStart) * 86400) >= SpinEdit1.Value THEN
      Self.Close
  ELSE
      Edit1.Text := FloatToStr(Round((Now - IdleStart) * 86400));
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
    IdleStart := Now;
end;

end.