C#如何让同一个窗口只能打开一次和一个程序只能同时打开一个

1、C#如何让同一个窗口只能打开一次
public Form2()

{

InitializeComponent();

}

private static Form2 f2 = new Form2();

public static Form2 getf2()

{

if (f2.IsDisposed)

{

f2 = new Form2();

return f2;

}

else

{

return f2;

}

}

form1中的
private void button1_Click(object sender, EventArgs e)

{

Form2.getf2().Show();

Form2.getf2().Activate();
}
//=====创建互斥体法：=====

//bool blnIsRunning;

//Mutex mutexApp = new Mutex(false, Assembly.GetExecutingAssembly().FullName, out blnIsRunning);

//if (!blnIsRunning)

//{

// MessageBox.Show("程序已经运行！", "提示",

// MessageBoxButtons.OK, MessageBoxIcon.Exclamation);

// return;

//}

2、一个程序只能运行一个

//=====判断进程法：(修改程序名字后依然能执行)=====

Process current = Process.GetCurrentProcess();

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

foreach (Process process in processes)

{

if (process.Id != current.Id)

{

if (process.MainModule.FileName

== current.MainModule.FileName)

{

MessageBox.Show("程序已经运行！", Application.ProductName,

MessageBoxButtons.OK, MessageBoxIcon.Exclamation);

return;

}

}

}