private void widthValidation(object sender, CancelEventArgs e)
 {
     if ((width.Value < Desk.MINWIDTH || width.Value > Desk.MAXWIDTH) && !(Char.IsDigit((char)width.Value)))
     {
         width.Text = String.Empty;
         invalid f = new invalid();
         f.Show(this);
     }
 }
 private void drawerValidation(object sender, EventArgs e)
 {
     if (drawer.Value > Desk.MAXDRAWERS)
     {
         drawer.Text = String.Empty;
         invalid f = new invalid();
         f.Show(this);
     }
 }
 private void depthValidation(object sender, EventArgs e)
 {
     if (depth.Value < Desk.MINDEPTH || depth.Value > Desk.MAXDEPTH)
     {
         depth.Text = String.Empty;
         invalid f = new invalid();
         f.Show(this);
     }
 }