private void ruleListView_MouseDoubleClick(object sender, MouseButtonEventArgs e)
        {
            ListViewItem item = Utilities.GetVisualParent<ListViewItem>((UIElement)Mouse.DirectlyOver);
            if (item == null) return;
            Cdsrule rule = item.Content as Cdsrule;
            if (rule != null)
            {
                cdsruleG = rule;
                EditCdsrule(rule);
            }
        }