C#

using System;
using System.Windows.Forms;

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private void buttonShowForm2_Click(object sender, EventArgs e)
    {
        Form2 form2 = new Form2();
        form2.DoUpdate += new EventHandler(form2_DoUpdate);
        form2.Show();
    }

    void form2_DoUpdate(object sender, EventArgs e)
    {
        // Do your thing here
        Console.Write("Update");
    }
}

using System;
using System.Windows.Forms;

public partial class Form2 : Form
{
    public event EventHandler DoUpdate;

    public Form2()
    {
        InitializeComponent();
    }

    void buttonUpdate_Click(object sender, EventArgs e)
    {
        OnDoUpdate(EventArgs.Empty);
    }

    protected virtual void OnDoUpdate(EventArgs e)
    {
        EventHandler eh = DoUpdate;
        if (eh != null)
            eh(this, e);
        Close();
    }
}

static class EventHandler
    {
        static Action Event; // the global state
        public static void SetGlobalEvent(Action a) // Setts the event
        {
            Event = a;
        }
        public static void Execute_Event() // Execute the event
        {
            Event();
        }


    }

    class Form1
    {
        public Form1()
        {
            EventHandler.SetGlobalEvent(Event); // Sett the event
        }

        public void Event() // The events that going to be executet
        {
            var x = 2 + 2;
        }
    }

    class Form2
    {
        public void Onclick()
        {
            EventHandler.Execute_Event(); // Execute the event
            this.Destroy(); // Destroy your form ( or close )
        }
    }

Patrik.karlin wrote:

if form1 creates form2 you can pass
in "this" from form1 as a parameter

DaveyM69 wrote:

... but now you're starting to couple unrelated classes - not a great idea. The easiest, sure - but best avoided.

Dave Kreskowiak wrote:

You're looking for the ASP.NET forum