Run one instance from the application

Question

I have a windows application (C#) and i need to configure it to run one instance from the application at the time , It means that one user clicked the .exe file and the appl

Answer 1

The VB.Net team has already implemented a solution. You will need to take a dependency on Microsoft.VisualBasic.dll, but if that doesn't bother you, then this is a good solution IMHO. See the end of the following article: Single-Instance Apps

Here's the relevant parts from the article:

1) Add a reference to Microsoft.VisualBasic.dll 2) Add the following class to your project.

public class SingleInstanceApplication : WindowsFormsApplicationBase
{
    private SingleInstanceApplication()
    {
        base.IsSingleInstance = true;
    }

    public static void Run(Form f, StartupNextInstanceEventHandler startupHandler)
    {
        SingleInstanceApplication app = new SingleInstanceApplication();
        app.MainForm = f;
        app.StartupNextInstance += startupHandler;
        app.Run(Environment.GetCommandLineArgs());
    }
}

Open Program.cs and add the following using statement:

using Microsoft.VisualBasic.ApplicationServices;

Change the class to the following:

static class Program
{
    /// 

    /// The main entry point for the application.
    /// 
    [STAThread]
    static void Main()
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        SingleInstanceApplication.Run(new Form1(), StartupNextInstanceEventHandler);
    }

    public static void StartupNextInstanceEventHandler(object sender, StartupNextInstanceEventArgs e)
    {
        MessageBox.Show("New instance");
    }
}