private void Sel_FormClosing(object sender, FormClosingEventArgs e)
 {
     if (select.SelectedArea)
     {
         lastFormLocation = select.Location;
         var offsetLocation = new Point(select.Location.X + 7, select.Location.Y + select.TitleHeight);
         selectionRectangle = new Rectangle(offsetLocation, select.Size);
     }
     select = null;
 }
 private void btnSelect_Click(object sender, EventArgs e)
 {
     if (select == null)
     {
         select = new RectangleSelect();
         if (selectionRectangle != null)
         {
             //select.Location = lastFormLocation;
         }
         select.FormClosing += Sel_FormClosing;
         select.Show();
     }
 }