gistfile1.txt

using System;
using System.Drawing;
using System.Windows.Forms;

public class Test
{
    static void Main()
    {
        Button button = new Button
        { 
            Text = "Click",
            Location = new Point(10, 50)
        };
        ListBox list = new ListBox
        {
            Items = { "first", "second", "third" },
            Location = new Point(10, 100),
            SelectionMode = SelectionMode.MultiExtended
        };
        button.Click += delegate
        {
            Console.WriteLine("Selected items:");
            foreach (var item in list.SelectedItems)
            {
                Console.WriteLine(item);
            }
        };
        Form form = new Form
        {
            Size = new Size(300, 300),
            Controls = { button, list }
        };
        Application.Run(form);
    }
}