C#

public partial class Form1 : Form
{
  public delegate void FooHandler(int myParam1, string myParam2);
  public static FooHandler fooHandler;

  public Form1()
  {
    InitializeComponent();
    fooHandler = foo;

    Form2 f = new Form2();
    f.Show();
  }

  public void foo(int myParam1, string myParam2)
  {
    MessageBox.Show(string.Format("foo {0},{1}", myParam1, myParam2));
    this.Text = "I was foo-ed";
  }
}
public partial class Form2 : Form
{
  public Form2()
  {
    InitializeComponent();
    this.button1.Click += new EventHandler(button1_Click);
  }

  private void button1_Click(object sender, EventArgs e)
  {
    if (Form1.fooHandler != null) Form1.fooHandler(2, "foo-you!");
  }
}

public void OpenNewMap(object sender, EventArgs e)
        {


            frmNewMap.ShowDialog();
            if (frmNewMap.OkClicked)
            {
                tileset = frmNewMap.tileset;
                texture = Texture2DFromFile(frmNewMap.TilesetTextureName);
                tilesetBitmap = Bitmap.FromFile(frmNewMap.TilesetTextureName);
                tileMap = new TileMap(frmNewMap.MapWidth, frmNewMap.MapHeight);
                layerToolStripMenuItem.Enabled = true;
                saveMapToolStripMenuItem.Enabled = true;
                clbLayers.Items.Add(frmNewMap.TileLayerName, true);
                clbLayers.SelectedIndex = 0;
                clbLayers.SelectionMode = SelectionMode.One;
                currentLayer = tileMap.layers[0];
                FillPictureBox(0);
                form2.nudCurrentTile.Value = 0;                  //these commands
                form2.nudCurrentTile.Maximum = tileset.tiles.Count - 1; // and this
                this.Invalidate();
            }
        }

Varun Thakur wrote:

abstract keyword is an indication to compiler not to consider the abstract class as a type.

Varun Thakur wrote:

If any it is just for initialization of properties/variables of abstract class then that can be achieved by private or protected constructor.

Varun Thakur wrote:

If you declare a public constructor in an abstract class then compiler will not give any errors.

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]