让程序只运行一个实例的方法

让程序只运行一个实例的方法一：

static void Main()

{

System.Threading.Mutex mutex;

bool isNew;

mutex = new System.Threading.Mutex(true, "myproject", out isNew);

if (isNew)

{

Application.EnableVisualStyles();

Application.SetCompatibleTextRenderingDefault(false);

Application.Run(new Login());

}

else

{

MessageBox.Show("本程序已经在运行！","提示信息",MessageBoxButtons.OK,MessageBoxIcon.Warning);

}

}

让程序只运行一个实例的方法二（会显示正在运行的窗口）：

static void Main()

{

Process instance = RunningInstance();

if (instance == null)

{

Application.EnableVisualStyles();

Application.SetCompatibleTextRenderingDefault(false);

Application.Run(new Login());

}

else

{

HandleRunningInstance(instance);

}

}

//返回正在运行的程序进程

public static Process RunningInstance()

{

Process current = Process.GetCurrentProcess();

Process[] processes = Process.GetProcessesByName(current.ProcessName);

foreach (Process process in processes)

{

if (process.Id != current.Id)

{

if (Assembly.GetExecutingAssembly().Location.Replace("/ ", "\\ ") == current.MainModule.FileName)

{

return process;

}

}

}

return null;//第一次运行，返回null

}

//显示正在运行的进程当前窗口

public static void HandleRunningInstance(Process instance)

{

ShowWindowAsync(instance.MainWindowHandle, WS_SHOWNORMAL); //置窗口为正常状态

SetForegroundWindow(instance.MainWindowHandle);

}

#region 调用系统api

[DllImport("User32.dll ")]

private static extern bool ShowWindowAsync(IntPtr hWnd, int cmdShow);

[DllImport("User32.dll ")]

private static extern bool SetForegroundWindow(IntPtr hWnd);

private const int WS_SHOWNORMAL = 1;

#endregion