private void menuPLZoomTo_Click(object sender, EventArgs e)
        {
            MDIChild mc = this.ActiveMdiChild as MDIChild;

            if (mc == null)
            {
                return;
            }

            ZoomTo dlg = new ZoomTo(mc.Viewer);

            dlg.StartPosition = FormStartPosition.CenterParent;
            dlg.ShowDialog();
        }
		private void menuPLZoomTo_Click(object sender, EventArgs e)
		{
			MDIChild mc = this.ActiveMdiChild as MDIChild;
			if (mc == null)				 
				return;

			ZoomTo dlg = new ZoomTo(mc.Viewer);
			dlg.StartPosition = FormStartPosition.CenterParent;
			dlg.ShowDialog();
		}