Mega Code Archive
How to control the behaviour of the PC PowerOnOff button (APM)
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Title: How to control the behaviour of the PC PowerOn/Off button (APM)
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms,
Menus, ShellApi, ExtCtrls, Dialogs;
type
TPowerButton = class(TComponent)
private
FHooked: Boolean;
FOnPowerbuttonPress: TNotifyEvent;
PPowerOffEnable: Boolean;
function MessageHook(var Msg: TMessage): Boolean;
protected
procedure DoPowerbuttonPress; dynamic;
public
Version, Hersteller: string;
IResultHi, IResultLo, ILParamHi, ILParamLo, IWParamHi, ILParam,
IWParamLo, IWparam, Imsg, IResult: Integer;
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
published
{events}
property OnPowerbuttonPress: TNotifyEvent
read FOnPowerbuttonPress write FOnPowerbuttonPress;
{properties}
property PowerOffEnable: Boolean read PPowerOffEnable write PPowerOffEnable;
end;
procedure Register;
implementation
const
PBT_APMQUERYSUSPEND = 536; {Request for permission to suspend.}
procedure Register;
begin
RegisterComponents('Zus?tzlich', [TPowerButton]);
end;
constructor TPowerButton.Create(AOwner: TComponent);
begin
inherited Create(AOwner);
Version := '1.0.0.0';
Hersteller := 'CTVNet.ch';
FHooked := False;
if not (csDesigning in ComponentState) then
begin
Application.HookMainWindow(MessageHook);
FHooked := True;
end;
end;
procedure TPowerButton.DoPowerbuttonPress;
begin
if Assigned(FOnPowerbuttonPress) then FOnPowerbuttonPress(Self);
end;
function TPowerButton.MessageHook(var Msg: TMessage): Boolean;
begin
IResultHi := Msg.ResultHi;
IResultLo := Msg.ResultLo;
ILParamHi := Msg.LParamHi;
ILParamLo := Msg.LParamLo;
IWParamHi := Msg.WParamHi;
ILParam := Msg.lParam;
IWParamLo := Msg.WParamLo;
Imsg := Msg.Msg;
IResult := Msg.Result;
IWparam := Msg.wParam;
if (Msg.Msg = PBT_APMQUERYSUSPEND) and (Msg.wParam = 0) then //win95/98
begin
if PPowerOffEnable = False then
begin
Msg.Result := PWR_FAIL;
end;
end;
if (Msg.Msg = PBT_APMQUERYSUSPEND) and (Msg.wParam = 0) then //winNT,2k,XP
begin
if PPowerOffEnable = False then
begin
Msg.Result := BROADCAST_QUERY_DENY;
end;
end;
if (Msg.Msg = PBT_APMQUERYSUSPEND) and (Msg.wParam = 0) then //excute Event
begin
DoPowerbuttonPress;
end;
end;
destructor TPowerButton.Destroy;
begin
if FHooked then Application.UnhookMainWindow(MessageHook);
inherited Destroy;
end;
end.
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