private void button2_Click(object sender, System.EventArgs e)
        {
            //Find the legend
            IElement element = axPageLayoutControl1.FindElementByName("Legend", 1);

            if (element != null)
            {
                //Delete the legend
                IGraphicsContainer graphicsContainer = axPageLayoutControl1.GraphicsContainer;
                graphicsContainer.DeleteElement(element);
                //Refresh the display
                axPageLayoutControl1.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewGraphics, null, null);

                //enable/disable buttons
                cmdDraw.Enabled       = true;
                cmdDelete.Enabled     = false;
                cmdChangeArea.Enabled = false;
                cmdChangeLine.Enabled = false;
            }
        }