如何在程序启动时，判断是否已经有同一个.exe在运行？

[chenwencheng]

防止用户打开两个相同的本应用程序

[codecb]

//---------------------------------------------------------------------------
#include <vcl\vcl.h>
#pragma hdrstop
//---------------------------------------------------------------------------
USEFORM("Unit1.cpp", Form1);
USERES("SingleInstance.res");
//---------------------------------------------------------------------------
WINAPI WinMain(HINSTANCE, HINSTANCE, LPSTR, int)
{
HANDLE mutex ;
try
{
const char mutexname [] = "SingleInstanceProgram" ;
// See if the mutex already exists.
mutex = OpenMutex (0, false, mutexname) ;
if (mutex == NULL)
{
// The mutex is not there. This means another instance of the program is
// not already running. Create the mutex so any other instance of the
// program will know that this one is already running.
mutex = CreateMutex (NULL, true, mutexname) ;
}
else
{
// The mutex exists so another instance of the program is running
// OR some other program created a mutex called "SingleInstanceProgram".
ShowMessage ("Application Already Running") ;
// Returning from WinMain terminates the program.
return 0 ;
}

Application->Initialize();
Application->CreateForm(__classid(TForm1), &Form1);
Application->Run();
}
catch (Exception &exception)
{
Application->ShowException(&exception);
}
ReleaseMutex (mutex) ;
return 0;
}
//---------------------------------------------------------------------------

[Friecin]

//---------------------------------------------------------------------------

#include <vcl.h>
#include "FormSys.h"
#include "FormMain.h"
#pragma hdrstop
//---------------------------------------------------------------------------
USEFORM("FormSys.cpp", frmSys);
USEFORM("FormMain.cpp", frmMain);
USEFORM("DataMod.cpp", DMod); /* TDataModule: File Type */
USEFORM("FormEdit.cpp", frmEdit);
。。。。

WINAPI WinMain(HINSTANCE, HINSTANCE, LPSTR, int)
{
try
{
//这里创建一个互斥量（你就复制吧）！！！！！！！！！！！！！！！！！！！
HANDLE Mutex=OpenMutex(MUTEX_ALL_ACCESS,false,"OneInstanceAllowed");
if(Mutex==NULL) //this is the only instance
{
//Create the Mutex...
Mutex=CreateMutex(NULL,true,"OneInstanceAllowed");
}
else //this is not only instance
{
//Send a message to the previous instance of the application,and asking_
//it to restore and front itself.
SendMessage(HWND_BROADCAST,RegisterWindowMessage("OnlyOne"),0,0);
return 0;
}
//创建互斥结束

Application->Initialize();
Application->CreateForm(__classid(TDMod), &DMod);
Application->CreateForm(__classid(TfrmSys), &frmSys);
,GWL_STYLE);
}
catch (Exception &exception)
{
Application->ShowException(&exception);
}
catch (...)
{
try
{
throw Exception("");
}
catch (Exception &exception)
{
Application->ShowException(&exception);
}
}
return 0;
}
//---------------------------------------------------------------------------


工程主窗体中：
.h

public:

....
unsigned int msgRestore;
bool __fastcall MessageHandler(TMessage &Message);
BEGIN_MESSAGE_MAP
MESSAGE_HANDLER(WM_DROPFILES, TMessage, DragDropFiles);
END_MESSAGE_MAP(TForm);
...

.cpp

//创建系统消息，用于接受Mutex(互斥量)发送的消息
bool __fastcall TfrmSys::MessageHandler(TMessage &Message)
{
if(Message.Msg==msgRestore)
{
if(frmMain)
{
frmMain->Show();
frmMain->WindowState=wsMaximized;
}
else
Close();

Application->Restore();
Application->BringToFront();
return true;
}
else
return false;
}
//---------------------------------------------------------------------------

//窗体的OnCreate
void __fastcall TfrmSys::FormCreate(TObject *Sender)
{
//注册Onlyone到Mutex,并且设置应用程序与MessageHandler的消息挂钩
msgRestore=RegisterWindowMessage("onlyone");
Application->HookMainWindow(MessageHandler);
}

[Friecin]

哇！我来晚了~

[chenwencheng]

老兄，连第一个程序都自杀了啊。

[chenwencheng]

太长啦，我还没吃晚饭，都晕了。有没有短一点的啊？

[xiaoxing1978]

假设你的程序主窗口的caption为"exam"
if(Findow(NULL,"exam")!=0)
ShowMessage(该程序已运行");

[xiaoxing1978]

错了,是FindWindow

[yingyys]

使用互斥量，同上

[天马座的流星拳]

在你程序的WinMain的 try{ } 的上面加上：
HANDLE Mutex=OpenMutex(MUTEX_ALL_ACCESS,false,"OneInstanceAllowed");
if(Mutex==NULL)
{ Mutex=CreateMutex(NULL,true,"OneInstanceAllowed"); }
else
{ SendMessage(HWND_BROADCAST,RegisterWindowMessage("OnlyOne"),0,0);
return 0;//有多个程序实例，退出
}
偷的楼上的，用互斥量最保险、最快。

[zbc]

体力活，呵呵

[winterxu416]

关注互斥量