C#

private void textBox1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
if(e.KeyChar < 48 || e.KeyChar > 57 )
   e.Handled = true;
}

public EventHandler ButtonA_Click
{
  add
  {
    buttona.Click += new EventHandler(value);
  }
  remove
  {
    buttona.Click -= new EventHandler(value);
  }
}

public class ProcessListViewItem : ListViewItem
{
  public readonly Process Process;
  public ProcessListViewItem(Process p) : this(p.ProcessName)
  {
    Process = p;
  }
}

Process [] Processes = Process.GetProcesses();
 
foreach( Process p in Processes )
{
  myListView.Items.Add( new ProcessListViewItem(p) );
}

CSettingsDialog dlg = new CSettingsDialog();
dlg.ShowDialog();
}