private void НовыйДокументToolStripMenuItem_Click(object sender, EventArgs e)
        {
            const int visualFeedbackOn = 1;
            const int visualFeedbackOff = 0;

            Microsoft.Office.Interop.Visio.Application visioApplication;

            // Only one document can be open.
            visioApplication = (Microsoft.Office.Interop.Visio.Application)axDrawingControl1.Window.Application;
            axDrawingControl1.Src = "";

            // Get the current state of the visual feedback. If visual
            // feedback is on the end user will see changes in the drawing
            // window as the code operates on the shapes.
            int visualFeedbackStatus = visioApplication.ScreenUpdating;

            // Don't let the user see the visual feedback while the shapes
            // are deleted.
            if (visualFeedbackStatus == visualFeedbackOn)
            {
                visioApplication.ScreenUpdating = visualFeedbackOff;
            }

            // Delete all of the shapes from the Visio window.
            // Note: when invoking Selection.Delete(), the EventSink class will raise
            // an event and call onRemoveProductInformation for each shape deleted
            // from the page. That will update the product data and grid control.
            Window targetWindow;
            targetWindow = (Window)axDrawingControl1.Window;
            if (targetWindow.PageAsObj.Shapes.Count > 0)
            {
                targetWindow.SelectAll();
                targetWindow.Selection.Delete();
            }

            // Set the document saved flag since the drawing control is now
            // displaying a blank document.
            axDrawingControl1.Document.Saved = true;

            // Restore the screen updating status.
            if (visualFeedbackStatus == visualFeedbackOn)
            {
                visioApplication.ScreenUpdating = visualFeedbackOn;
            }
        }
    }

targetWindow.Selection.Delete();