将应用程序注册到URI方案

Question

I have a wpf app I have registered as a URI Scheme by doing the following.

HKEY_CLASSES_ROOT
-->myappname
   -->shell
      -->open
         -->command
            (Default) = "c:\pathtomyapp\app.exe"

Fantastic! However, my application enforces that only one instance can run at a time. How can I detect that my app is already running and for example bring it to the foreground?

Answer 1

You can use a named mutex to detect that application is already running. Or, if you have a GUI app, you can inherit your form from VisualBasic's SingleInstance application , and it will do routhgly the same for you.

  public class SingleInstanceController
    : WindowsFormsApplicationBase
  {
    public SingleInstanceController()
    {
      // Set whether the application is single instance
      this.IsSingleInstance = true;

      this.StartupNextInstance += new
        StartupNextInstanceEventHandler(this_StartupNextInstance);
    }

    void this_StartupNextInstance(object sender, StartupNextInstanceEventArgs e)
    {
      // Here you get the control when any other instance is
      // invoked apart from the first one.
      // You have args here in e.CommandLine.

      // You custom code which should be run on other instances
    }

    protected override void OnCreateMainForm()
    {
      // Instantiate your main application form
      this.MainForm = new Form1();
    }
  }

[STAThread]
static void Main(string[] args)
{    
  SingleInstanceController controller = new SingleInstanceController();
  controller.Run(args);
}

It does not matter whenever you write your code in C#, as this class is avaliable as a part of .Net framework and for all languages.

And here is a wrapper for the WPF