How can I prevent launching my app multiple times?

Question

I deployed my C# WinForms application using ClickOnce installation. Everything works fine with it (after a lot of work) :), but now I\'m facing a problem:

Whenever

Answer 1

In WPF, you can use this code in your App.xaml.cs file:

private static System.Threading.Mutex _mutex = null;

protected override void OnStartup(StartupEventArgs e)
{
    string mutexId = ((System.Runtime.InteropServices.GuidAttribute)System.Reflection.Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(System.Runtime.InteropServices.GuidAttribute), false).GetValue(0)).Value.ToString();
    _mutex = new System.Threading.Mutex(true, mutexId, out bool createdNew);
    if (!createdNew) Current.Shutdown();
    else Exit += CloseMutexHandler;
    base.OnStartup(e);
}
protected virtual void CloseMutexHandler(object sender, EventArgs e)
{
    _mutex?.Close();
}

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• https://www.c-sharpcorner.com/UploadFile/f9f215/how-to-restrict-the-application-to-just-one-instance/
• https://social.msdn.microsoft.com/Forums/vstudio/en-US/eced1b92-43c5-405d-84b1-780e774c9d3e/how-can-i-prevent-launching-my-app-multiple-times?forum=wpf