用Mutex实现程序单实例运行无效的问题

[cncrazyzz]

[STAThread]
static void Main()
{
bool createdNew = false;
Mutex _mutex = new Mutex(true, "AddBook", out createdNew);//互斥

if (!createdNew)
{
MessageBox.Show("请不要重复运行程序");
return;
}

Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new mainFM());
}

是参考的网上写的，可是我多次运行的时候createdNew始终是true，请高手指点！

[rainingheart]

多次运行如多次按F5,还是一次一个
你运行两次exe试下

[捷哥1999]

看看这个例子：
http://www.paiming.org/bbs/read.php?tid=15611

[捷哥1999]

1. API函数的声明
[DllImport("User32.dll")])
private static extern bool ShowWindowAsync(IntPtr hWnd, int cmdShow);

// 0-Hidden, 1-Centered, 2-Minimized, 3-Maximized 
private const int WS_SHOWNORMAL = 3;

2. 查找并激活已经存在的程序(仅应用于进程名相同的程序)
private static bool ExistRunningInstance()
{ 
    Process currentProcess = Process.GetCurrentProcess();
    Process[] procList = Process.GetProcessesByName(currentProcess.ProcessName);

    foreach (Process proc in procList)
    { 
        // Found a running instance
        if (proc.Id != currentProcess.Id)
        { 
            // Active the running instance 3
            ShowWindowAsync(proc.MainWindowHandle, WS_SHOWNORMAL);
            SetForegroundWindow(proc.MainWindowHandle);

            return true;
        } 
    } 

    return false;
} 

3. 在Main函数入口判断
[STAThread]
static void Main()
{ 
    // Control only one instance with the same process name can run
    if (ExistRunningInstance())
    { 
        Environment.Exit(1);
    } 
}

[skep99]

我的是这么写的:

        [STAThread]
        static void Main()
        {

            Mutex mutex = new Mutex(false, "myForm");
            bool Running = !mutex.WaitOne(50, false);
            if (Running)
            {
                mutex.Close();
                MessageBox.Show("应用程序已经启动！");
                return;
            }

            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new Form3());
        }