Listing 2

// Registering standard event handlers
 for (i=0; i<panMain.Controls.Count; i++)
  for (j=0; j<panMain.Controls[i].Controls.Count; j++) { 
    ...
    ((SpecialLabel)panMain.Controls[i].Controls[j]).MouseDown
       += new MouseEventHandler(label_mousedown);
    ((SpecialLabel)panMain.Controls[i].Controls[j]).MouseUp
       += new MouseEventHandler(label_mouseup);
    ...