Delphi 防止程序多次运行《转》

//防止多次打开
unit MultInst;
interface
uses Windows ,Messages, SysUtils, Classes, Forms;
implementation
const
STR_UNIQUE
= '{2BE6D96E-827F-4BF9-B33E-8740412CDE96}';
MI_ACTIVEAPP
= 1;
{激活应用程序}
MI_GETHANDLE
= 2;
{取得句柄}
var
iMessageID
: Integer;
OldWProc
: TFNWndProc;
MutHandle
: THandle;
BSMRecipients : DWORD;
function NewWndProc(Handle: HWND; Msg: Integer; wParam, lParam: Longint): Longint; stdcall;
begin
Result := 0;
if Msg = iMessageID then
begin
case wParam of
MI_ACTIVEAPP: {激活应用程序}
if lParam<>0 then
begin
{收到消息的激活前一个实例}
{为什么要在另一个程序中激活?}
{因为在同一个进程中SetForegroundWindow并不能把窗体提到最前}
if IsIconic(lParam) then
OpenIcon(lParam)
else
SetForegroundWindow(lParam);
Application.Terminate; {终止本实例}
end;
MI_GETHANDLE: {取得程序句柄}
begin
PostMessage(HWND(lParam), iMessageID, MI_ACTIVEAPP, Application.Handle);
end;
end;
end
else
Result := CallWindowProc(OldWProc, Handle, Msg, wParam, lParam);
end;
procedure InitInstance;
begin
{取代应用程序的消息处理}
OldWProc := TFNWndProc(SetWindowLong(Application.Handle, GWL_WNDPROC, Longint(@NewWndProc)));
{打开互斥对象}
MutHandle := OpenMutex(MUTEX_ALL_ACCESS, False, STR_UNIQUE);
if MutHandle = 0 then
begin
{建立互斥对象}
MutHandle := CreateMutex(nil, False, STR_UNIQUE);
end
else
begin
Application.ShowMainForm
:=
False;
{已经有程序实例,广播消息取得实例句柄}
BSMRecipients := BSM_APPLICATIONS;
BroadcastSystemMessage(BSF_POSTMESSAGE or BSF_POSTMESSAGE,@BSMRecipients,iMessageID,MI_GETHANDLE,Application.Handle);
//BroadCastSystemMessage(BSF_IGNORECURRENTTASK or BSF_POSTMESSAGE, @BSMRecipients, iMessageID, MI_GETHANDLE,Application.Handle);
end;
end;
initialization
{注册消息}
iMessageID
:= RegisterWindowMessage(STR_UNIQUE);
InitInstance;
finalization
{还原消息处理过程}
if OldWProc <> Nil then
SetWindowLong(Application.Handle, GWL_WNDPROC, LongInt(OldWProc));
{关闭互斥对象}
if MutHandle <> 0 then
CloseHandle(MutHandle);
end.

在XE7下测试通过.